Thermal retrofitting system for a radiator

Abstract

The present invention relates to a thermal retrofitting system for a radiator, applicable for updating said radiator such that it has heating and cooling capacity.

Description

OBJECT OF THE INVENTION

[0001] The present invention relates to a thermal retrofitting system for a radiator, applicable for updating said radiator such that it has heating and cooling capacity; as well as to a method for updating a radiator by means of the installation of said system. The invention can be intended for the thermal retrofitting of interior spaces of buildings, allowing the water circuit and radiators existing previously in said buildings to be maintained.BACKGROUND OF THE INVENTION

[0002] Construction context will change significantly in the coming years: new buildings are built to high efficiency standards and many resources are being mobilized to retrofit the thermal envelope of existing buildings. As a consequence, buildings will need less heating and more cooling, due to climate change and increased demand for comfort. Moreover, decarbonization means that existing fossil fuel boilers will no longer be installed and replaced, which encourages the installation of heat pumps in buildings.

[0003] Retrofitting work with improved thermal envelope can considerably reduce (by 30-40%) the demand for heating power, but this reduction is not the same in all spaces of a building. Moreover, an improved envelope may mean an increase in the need for cooling, which increases with climate change.

[0004] In view of the foregoing, it is necessary to provide alternatives that allow thermally retrofitting the interior spaces of buildings and dwellings, without the need to replace the water circuits and radiators already installed therein. Old buildings usually have a boiler that provides hot water to the radiator.

[0005] Heat pumps, which represent an alternative for replacing a boiler, for providing hot water to a radiator, are known in the state of the art. In this sense, the hot water in gas boilers is generally driven to the radiators at 70-75°C. Heat emission from the radiators greatly depends on this high temperature, such that their heat emission decreases considerably if this hot water driving temperature is lowered to a more moderate range (40-45°C).

[0006] Heat emission from the radiator depends on the temperature difference between the radiator (its average temperature) and the environment. If the temperature at which the fluid enters the radiator is expressed as t e , the temperature at which the fluid exits the radiator as t s , t m is the mean temperature of said radiator and is calculated as t m = t e + t s 2 , with t a being at room temperature, the heat emission (Q) of the radiator is given by the expression: Q = Q 50 ⋅ Δ T 50 n , where ΔT = t m - t a is the rise in temperature between the radiator and the environment, Q50 is the heat emission corresponding to normal conditions (to a rise in temperature of 50°C), and "n" is the exponent that depends on the geometry of the radiator (usually n=1.3). In general, the heat transfer fluid is water, such that in the following reference will be made exclusively to water as said fluid.

[0007] The thermal power that a radiator is capable of dissipating depends on the mass flow, but, above all, on the temperature reached by the heat transfer fluid, usually water.

[0008] The heat output that the radiator is capable of dissipating depends on the rise in temperature between the room environment (usually 20°C) and the mean temperature of the outer metal plate of the radiator.

[0009] For example, if the temperature of the water reaching the radiator decreases from 75°C to 40°C, for an environment at a temperature of 20°C, then heat emission from the radiator can be reduced by about 70%. In other words, if the boiler is changed for a heat pump, the temperature reached in the driving operation is generally lower. Surprisingly, some boiler pumps can reach 70°C, but with very poor performance.

[0010] The temperature at which a heat pump works with good performance is about 40°C. If the drive temperature (the one that reaches the radiator) goes from 75 to 40°C, the thermal power that the radiator is capable of dissipating is one third of what was originally intended.

[0011] Therefore, replacing boilers with heat pumps to provide hot water to radiators is not without problems, particularly, the reduction of heat emission. Furthermore, this replacement does not allow providing the radiator with cooling capacity.

[0012] Some of the major drawbacks of replacing boilers with aerothermal installations (i.e., using heat pumps) are as follows: i. if the intention is to keep the radiators, the performance of the equipment is very low, significantly increasing the electrical cost; ii. if the intention is to take advantage of the opportunity for cooling, it is necessary to change the radiators for fan coils or underfloor heating or cooling, which increases installation costs and time, in addition to causing greater environmental impact; and iii. when the external temperature drops (which is precisely when the use of heating is most needed), the heating capacity of the aerothermal system decreases, causing situations of thermal discomfort. In particular, when the external temperature drops, the temperature of the heat transfer fluid that will reach the radiator will be insufficient, as the aerothermal system will work worse.

[0013] In the case of replacing the heat boiler with a heat pump, it is possible to opt for vapor compression cycles at 70°C or for systems installed in the radiators themselves, referred to as boosters for said radiators. An example of these boosters is shown in document WO 2018 / 229314 A1, which allows increasing the convection and heat dissipation capacity of the radiator.

[0014] Boosters generally incorporate direct current fans that are intended to add a fan coil effect to the radiator, such that they can partially compensate for a lower water driving temperature. However, these boosters do not allow cooling, which makes it necessary to incorporate an additional AIR-AIR air conditioning system, increasing the impact of building retrofitting, both environmentally and visually on the façade. As is known in this technical field, an AIR-AIR air conditioning refers to the fact that the external unit is air (if it is air, it is a heat exchanger on the façade with the outside air; if it is water, it would be a geothermal system), and that the internal unit where it delivers the cold or heat is also air (therefore, an internal air unit would be a conventional air conditioning, while an internal water unit would be a water circuit with fan coils).

[0015] Alternatively, it is also possible to opt for a reversible heat pump (i.e., adding the cooling option). However, this alternative requires the incorporation of low-temperature emitters (underfloor heating and / or fan coils).

[0016] The invention provides a thermal retrofitting system which allows combining conventional radiators with heat pumps, additionally providing cooling capacity to said radiators and improving thermal efficiency.DESCRIPTION OF THE INVENTION

[0017] The present invention allows overcoming the limitations of the state of the art identified above by means of a thermal retrofitting system according to claim 1. The dependent claims define preferred embodiments of the invention.

[0018] In a first inventive aspect, the invention relates to a thermal retrofitting system for a radiator located in a room at room temperature, wherein the radiator is connected to a reversible heat pump, wherein the thermal retrofitting system comprises: a frame adapted to be coupled to the radiator; and one or more thermoelectric devices configured to be housed in said frame, wherein each of the one or more thermoelectric devices comprise two faces: ∘ a first face configured to be in thermal contact with the radiator, said first face being proximal to the radiator; and ∘ a second face, opposite the first face, which is configured to be in thermal contact with the frame, said second face being proximal to the frame; and one or more fans configured to be housed in the frame; a thermovalve adapted to be arranged in a fluid inlet of the radiator; a heat transfer fluid flow control module configured to operate the thermovalve and to set the flow rate of heat transfer fluid entering through the fluid inlet of the radiator; a processing and regulating unit configured to communicate with the reversible heat pump and with the heat transfer fluid flow control module; wherein the processing and regulating unit is configured to activate the reversible heat pump in a heating mode when the room temperature of the room is lower than a setpoint temperature to be reached and to activate the heat transfer fluid flow control module, and said heat transfer fluid flow control module is configured to open the thermovalve completely and to set the maximum flow rate of water available in the radiator as long as the setpoint temperature is not reached.

[0019] The thermal retrofitting system of the invention is useful in retrofitting the interior spaces of buildings and dwellings, when the heating and cooling systems thereof are to be updated without having to remove old radiators or make modifications to the water circuit available in the building. In the field of the invention, thermal retrofitting shall be understood as the conditioning and improvement of the functionality of a radiator.

[0020] In particular, the invention facilitates the replacement of gas boilers in buildings or dwellings with reversible heat pumps, preserving the water circuit and the radiators themselves which are already installed in said buildings or dwellings.

[0021] Moreover, heat pumps require a maximum temperature of about 40-45°C and they lose efficiency beyond said temperature. Therefore, directly replacing the gas boilers of the buildings with heat pumps is not an optimal solution since the maximum temperature of the heat pumps is insufficient for conventional radiators to perform suitably.

[0022] In this way, a first technical problem solved by the present invention is how to couple a heat pump to a conventional radiator as an alternative to a pre-existing boiler. In other words, the invention allows avoiding the problems of a poor heat emission that would result from the combination of a conventional radiator and a heat pump, allowing the heat pump to be an effective option in the retrofitting of buildings where the radiators and the water circuit are to be preserved.

[0023] Moreover, the invention solves a second technical problem: how to adapt a conventional radiator for cooling. Advantageously, this allows improving thermal comfort in the interior spaces of buildings without replacing said radiators, thereby avoiding the higher economical cost and execution time for retrofitting that would be entailed by opting for the installation of underfloor heating or fan coils.

[0024] It should be highlighted that the present invention solves both technical problems mentioned above simultaneously.

[0025] The thermal retrofitting system of the invention has two operating modes: a heating mode and a cooling mode, that will depend on whether the reversible heat pump is operating in the heating or cooling mode. In the invention, it shall be understood that the pump operates in the heating mode when the setpoint temperature to be reached in the room is higher than room temperature, and in the cooling mode when the setpoint temperature to be reached in the room is lower than room temperature. In both cases, the thermal retrofitting system acts by boosting the heating or cooling provided by the reversible heat pump, in order to shorten the time to reach said setpoint temperature.

[0026] Therefore, in the present invention, the thermoelectric devices are used to raise the drive temperature without the heat pump having to work at a higher temperature. The invention allows compensating for the decrease in heat emission when the boiler is to be replaced with a heat pump to work together with conventional radiators.

[0027] A differential element with respect to the state of the art is the use of thermoelectric devices to serve as a support when the temperature of the water reaching the radiator is insufficient to provide the power that it needs to generate the necessary heat emission that arises the temperature of the room to a setpoint temperature.

[0028] In this way, the invention allows regulating the heat pump in the best way possible, performing a different regulation in each room based on needs, and boosting heat production if the production system does not allow same (in the case of an aerothermal heat pump and extreme external temperatures). Moreover, it allows the radiator to work in the cooling mode and even as a dehumidifier, a use that is not originally intended for the radiators.

[0029] The invention comprises a frame which is installed on the existing radiator. There are housed in the frame one or more thermoelectric devices having two faces or surfaces: with one face providing cooling and another face providing heating. The thermoelectric devices pump heat between their two faces, such that, in the heat mode, when the radiator is circulating low-temperature water (for example, 40°C), the thermoelectric device will raise the temperature of its hot side (in contact with the metal plate covering the radiator, and which is exposed) to 70°C, delivering more heating power which will be regulated in a very precise manner by means of the supply voltage of the thermoelectric devices.

[0030] When the boiler is replaced with a heat pump, the thermal retrofitting system can work in the heating mode and in the cooling mode. However, the problem arises from the mere replacement of the boiler with the heat pump is as follows: On one hand, in the heating mode the temperature at which hot water is driven is significantly lower than the temperature that can be reached in a boiler. If the drive temperature in a gas boiler is of about 70-75°C, the common drive temperature in a heat pump is 40-45°C. This implies the need to replace radiators with fan coils or to install underfloor heating, given that the necessary heat emission power is not achieved with this temperature. There are special heat pumps to raise this drive temperature, but their performance is significantly inferior, and furthermore, in this case, they are not capable of working in the cooling mode. On the other hand, conventional radiators are only intended for the diffusion of heat, not cold.

[0031] The proposed thermal retrofitting system overcomes these problems. The present invention allows changing a boiler for a heat pump by reusing the hydraulic ring of pre-existing radiators in the room or dwelling, for the diffusion of both heat and cold. The invention replaces the operation of a gas boiler for heating by distributing heat through a water circuit and emitting the same heat through radiators.

[0032] Additionally, if the temperature is regulated to sufficiently lower it, water condensation may even occur such that the room is dehumidified.

[0033] In the field of the present invention, it shall be understood that the mentioned thermoelectric devices are based on Seebeck effect. This invention proposes an additional heat pumping between the surface of the radiator and the frame, as a result of the thermoelectric devices, which maintain a temperature difference between their faces approximately proportional to a supply voltage applied thereto, as a result of Seebeck effect. In this way, the surface of the thermoelectric device in contact with the radiator will be colder than the surface of the radiator, absorbing heat, while the surface of the thermoelectric device in contact with the frame will be hotter than said frame, dissipating heat. The temperature of the frame will increase in those conditions with respect to the environment, increasing its heat diffusion capacity (with the help of fans, when they are present in certain embodiments of the invention, which will reduce the coefficient of convection).

[0034] In another preferred embodiment, the heat transfer fluid flow control module of the thermal retrofitting system is configured to provide values of the flow rate of the heat transfer fluid entering the radiator of between 300 and 1000 l / hour.

[0035] In this embodiment, the maximum flow rate (1000 l / hour) occurs when the thermovalve is completely open.

[0036] The invention comprises one or more thermovalves (also referred to as thermostatic valves), which can regulate the flow rate of water going through the radiator. Advantageously, this thermovalve can be closed, hindering the flow of water when there is no need for heating / cooling (for example, when an area is not occupied or it has been determined that temperature control is not necessary), while it can be gradually opened according to temperature control needs. The definitive value of the flow rate of heat transfer fluid depends on the total head loss of the hydraulic circuit and of the specific drive pump that has been installed.

[0037] Advantageously, certain embodiments of the invention allows the possibility of regulating three elements (thermoelectric devices, fans, and thermovalve) in a coordinated manner to control the temperature of the room (heating, cooling, and dehumidifying) precisely and in accordance with the needs of the space (which can be different from the spaces the temperatures of which are controlled by the rest of the radiators within the same water distribution loop).

[0038] Thermovalves are devices which regulate the opening of the valve for the entry of fluid to the radiator, and therefore regulate the flow rate of heat transfer fluid between a cold and / or heat emission source (a reversible heat pump) and the radiator. The flow rate will depend on the water circuit installation existing in the building where the thermal retrofitting system of the invention is installed.

[0039] Advantageously, the invention is coupled in existing radiators, which allows increasing the heat provided by each of the radiators individually (as a result of the control of thermovalve and the thermoelectric devices based on the actual need of the room), as well as adding to said radiators a second use as a cooling unit (as a result of the installation of fans and thermoelectricity) and a dehumidifier (with condensation collection), adapting to the use and comfort circumstances required.

[0040] In preferred embodiments, the thermal retrofitting system further comprises: a control module for the fans configured to operate the fans and to establish the range of revolutions of said fans; wherein the processing and regulating unit is configured to communicate with the control module for the fans and to activate said control module when the room temperature of the room is lower than a setpoint temperature if at least one preestablished heating ramp is not reached after a first predetermined time from the activation of the heat pump in the heating mode and the opening of the thermovalve has elapsed.

[0041] In preferred embodiments, the control module for the fans is further configured to increase the range of revolutions of said fans every first predetermined time if the heating ramp is not reached.

[0042] Advantageously, this embodiment allows gradually increasing the speed of the fans based on whether or not the heating ramp has been reached, at least until the setpoint temperature is reached.

[0043] In preferred embodiments, the thermal retrofitting system comprises one or more fans. The number of fans will depend on the width of the radiator in which the thermal retrofitting system will be installed, as well as on the heat emission required in the room. Preferably, the number of fans in the radiator is comprised in the range of 2-8. In even more preferred embodiments, said fans are located inside the frame.

[0044] In preferred embodiments, the fans can be regulated in a range of speed of between 400 and 1500 rpm. In preferred embodiments, the fans are substantially rectangular and have a surface measuring 12 x 12 cm 2< . In preferred embodiments, the fans are continuously powered at voltages of 12 V. In certain embodiments, the fans do not exceed 1000 rpm, so that they work silently.

[0045] In preferred embodiments, the fans are regulated by means of a pulse width modulation signal (PWM signal).

[0046] In preferred embodiments, the thermal retrofitting system is characterized in that: the control module for the fans is configured to establish the range of revolutions of between 400 and 1500 rpm; the preestablished heating ramp is 0.5°C / h; the first predetermined time is 0.25 h; and / or the increase in the range of revolutions of the fans every first predetermined time is at least 450 rpm.

[0047] In some of these embodiments, a gradual increase of the revolutions of the fans is applied.

[0048] In a preferred embodiment, the thermal retrofitting system further comprises: a power supply module for the thermoelectric devices configured to provide the supply voltage of the thermoelectric devices and to regulate the supply voltage of the thermoelectric devices as long as the setpoint temperature is not reached; wherein the processing and regulating unit is configured to activate the power supply module for the thermoelectric devices when the room temperature of the room is lower than a setpoint temperature if at least the preestablished heating ramp is not reached after the first predetermined time from the activation of the reversible heat pump in the heating mode and the opening of the thermovalve has elapsed at least twice.

[0049] Advantageously, this embodiment allows adjusting the different mechanisms of the thermal retrofitting system based on the speed with which the room is being heated to reach the setpoint temperature: first, operation is performed exclusively on the flow rate of heat transfer fluid of the radiators; if the above is not sufficient, the fans are also activated, increasing their range of revolutions gradually; and finally, if the two preceding points are not enough, the thermoelectric devices are additionally activated in an auxiliary manner to achieve the desired heating.

[0050] In a preferred embodiment, the processing and regulating unit is configured to regulate the flow rate of heat transfer fluid based on the temperature of the room where the radiator is located and on the setpoint temperature to be reached in said room.

[0051] In an embodiment of the thermal retrofitting system: the processing and regulating unit is configured to activate the reversible heat pump in a cooling mode when the room temperature of the room is higher than the setpoint temperature to be reached, such that the processing and regulating unit is configured to activate the heat transfer fluid flow control module, to completely open the thermovalve, and to set the maximum flow rate of water available in the radiator as long as the setpoint temperature is not reached; and the control module for the fans is configured to operate at the maximum range of revolutions of said fans as long as the setpoint temperature is not reached.

[0052] Advantageously, this embodiment also utilizes the cooling mode of the reversible heat pump. In this case, given that the temperature of the room is to be reduced, the fans are actuated at maximum from the start in order to reach the setpoint temperature as soon as possible.

[0053] In the cooling mode the radiator will receive cold water from the circulation pump through the water circuit. The radiator is not designed for cooling, so it is not capable of cooling the air of the spaces effectively. However, with the installation of the thermoelectric devices, the temperature of the face in contact with the metal plate can be lowered, increasing its cooling capacity. The cold water, like the hot water, goes through the radiator. In this case, it absorbs part of the heat and heats up. The heat which it is capable of absorbing (and therefore, cooling the room) also depends on the rise in temperature between the mean temperature of the radiator and the room, except that, in the case of cooling, this rise in temperature is barely 10-15°C. This system increases the cooling capacity, firstly as a result of the fans which, by increasing the coefficient of convection, increase the heat that is exchanged, and secondly, as a result of the thermoelectric devices which lower the temperature of the outer metal plate, and therefore increase the cooling capacity. Therefore, the combined action of the fans and the thermoelectric devices of the invention increase cooling capacity.

[0054] Advantageously, the thermal retrofitting system of the present invention comprises a smart frame which, coupled on the existing radiators, allows giving this equipment a second life, pumping heat between the radiator and the casing with thermoelectric technology, improving their heat diffusion capacity and adding cold diffusion capacity.

[0055] In a preferred embodiment of the thermal retrofitting system: the processing and regulating unit is configured to activate the power supply module for the thermoelectric devices when the room temperature of the room is higher than a setpoint temperature if a preestablished cooling ramp is not reached after a second predetermined time from the activation of the reversible heat pump in the cooling mode and the opening of the thermovalve has elapsed.

[0056] Advantageously, this embodiment includes the activation of the thermoelectric devices to achieve an additional cooling of the room if the activation of the heat pump in the cooling mode and the activation of the fans at maximum speed are not sufficient for cooling the room at a suitable speed.

[0057] In a preferred embodiment of the thermal retrofitting system: the preestablished cooling ramp is -0.5°C / h; and / or the second predetermined time is 0.25 h.

[0058] In this way, if the temperature of the room is not reduced at a suitable speed (in this embodiment, promoting at least a decrease of 0.5°C / h), then the thermoelectric devices are activated in an auxiliary manner.

[0059] In some embodiments, the first and second predetermined times coincide with one another. In other embodiments, the values of these parameters differ from one another.

[0060] In a preferred embodiment, the frame further comprises a condensate collection tray adapted to be arranged in the lower portion of the radiator.

[0061] In this preferred embodiment, when the invention works in the cooling mode, the outer metal plate of the radiator can cause water condensation. To that end, the condensate tray is arranged in the lower portion of the radiator to collect said water. In that sense, the thermal retrofitting system also add capacity for dehumidifying the room where the radiator is installed.

[0062] The capacity to lower air temperature depends on the humidity in the room where the invention is deployed. If the air is very humid (as is generally the case in coastal towns), when the temperature of the outer metal plate is below the dew temperature, condensation occurs. The thermoelectric devices allow regulation of the temperature of the outer metal plate, which facilitates dehumidification, if this is sought.

[0063] In preferred embodiments, the condensates collected in the condensate tray are lead to a drainage of the thermal retrofitting system. In alternative embodiments, the condensates are absorbed by means of a water retention system which is part of said embodiments of the invention. In these last embodiments, the water retention system comprises: a container made of sodium and / or potassium acrylate (materials capable of absorbing 250-500 times their weight in water); and / or one or more capillaries configured to discharge said condensates out of the thermal retrofitting system.

[0064] In preferred embodiments, the thermal retrofitting system further comprises: the reversible heat pump and / or the one or more radiators.

[0065] With respect to the control and regulating unit, it is configured to operate the following system control parameters in a coordinated manner: the flow rate of water of the radiator, the power of the thermoelectric devices (for example, regulating the supply voltage of said devices), the range of revolutions of one or more of the fans, etc. Advantageously, this allows adapting the radiator with the thermal retrofitting system according to the thermal needs of the space where it is installed.

[0066] In some embodiments of the invention, the temperature of the room will be regulated by modifying the supply voltage of the thermoelectric devices. The greater the difference between the temperature of the room and the setpoint temperature (or preestablished temperature for the room), the higher the supply voltage is. With a smaller difference, the supply voltage of the thermoelectric devices is reduced. In other words, the supply voltage of the thermoelectric devices is proportional to the temperature difference between the room (room temperature) and the preestablished temperature to be reached.

[0067] For example, a controller which acts on said supply voltage of proportional to the temperature difference between the setpoint temperature and the temperature of the room, or a PID controller, can be used for regulating the supply voltage of the thermoelectric devices.

[0068] In the embodiments in which a PID controller is used for regulating the power supply of the thermoelectric devices, said controller monitors three components: Proportional component: this will be the main term that applies a voltage based on the difference between the temperature of the room and the temperature set on the thermostat. Integral component: this term assesses the inertia of the system, increasing the voltage if the difference between the temperature of the room and the thermostat is constant over time. Derivative component: this term reduces the possible oscillation of the control, correcting the voltage in the case where the evolution of the temperature varies significantly at any given time.

[0069] In the embodiments with a PID controller, although the three components can be taken into account, the main component is the proportional component. In preferred embodiments of the invention, these three components are weighted, although the proportional component has a relative weight of between 0.8 and 0.9 (by 1) with respect to the total regulation applied. Advantageously, the use of the PID controller allows attenuating the regulation signal, although the use thereof is not essential for the operation of the invention.

[0070] In an example of the invention, the proportional component is about 3V / °C. In another embodiment, the integral component exhibits an integration time of 15 min and a derivative component very low (close to 0). However, in any case, these parameters must be configured based on temperature control needs.

[0071] Likewise, when the temperature of the room drops with respect to the setpoint temperature (which can be fixed, for example, by means of a thermostat, also included in preferred embodiments of the invention), the fans in those embodiments of the invention having said fans can also be activated. The installation of the fans in the frame favors the dissipation of heat (or cold), reducing thermal resistance, and therefore increasing heating (or cooling) capacity of the radiator. The rotational speed of the fans will be proportional to the temperature difference between the setpoint temperature and the room temperature in the room the temperature of which is to be controlled. Therefore, the power dissipated by the assembly of the radiator and the thermal retrofitting system is greater the higher the supply voltage applied on the thermoelectric devices is and the higher the rotational speed of the fans is.

[0072] In the invention, the number of thermoelectric devices depends on the heat emission required of the improved radiator with the thermal retrofitting system, as well as on the width of the frame.

[0073] In preferred embodiments, the thermoelectric devices are powered with voltages between 0 and 12 V and the heat emission is virtually proportional to the supply voltage.

[0074] In a more preferred embodiment, the processing and regulating unit of the thermal retrofitting system comprises a controller configured to regulate the flow rate of heat transfer fluid, the supply voltage of the thermoelectric devices, and / or the range of revolutions of the fans function in a manner proportional to the temperature difference between the radiator and the environment of the room.

[0075] In one embodiment, the thermal retrofitting system comprises a PID controller configured to regulate the control parameters in a manner proportional to the temperature difference between the radiator and the environment of the room. In these embodiments, the supply voltage applied will be regulated by means of a PID controller where the proportional term prevails, such that the voltage applied will depend on the difference between the temperature of the room and the preestablished setpoint temperature.

[0076] In preferred embodiments, the thermal retrofitting system comprises: one or more presence sensors installed in the room where the radiator is located and communicated with the processing and regulating unit, configured to detect the presence of people inside the room; a thermostat configured to establish a setpoint temperature to be reached in the room, said thermostat being communicated with the processing and regulating unit.

[0077] In preferred embodiments, the thermal retrofitting system comprises: one or more temperature sensors installed in one or more of the following locations: in the room, on at least one of the faces of the one or more thermoelectric devices, in the frame, in the heat transfer fluid inlet of the radiator, said temperature sensors being communicated with the processing and regulating unit.

[0078] In these embodiments with temperature sensors, the control and regulating unit is configured to continuously monitor the temperature of the room through the one or more temperature sensors (or probes) and to use the temperature measurements in the regulation of the thermal retrofitting system.

[0079] In preferred embodiments, the thermal retrofitting system comprises one or more of the following sensors: Temperature sensor for detecting the ambient temperature in the room. Temperature sensor for detecting the ambient temperature outside the room Temperature sensor for the heat transfer fluid. Temperature sensor for the outer face of the frame (in the outer casing).

[0080] In other embodiments, the thermal retrofitting system comprises one or more of the following sensors: Temperature sensor for the inner face of the thermoelectric device (i.e., the face of the thermoelectric device proximal to the radiator). Temperature sensor for the outer face of the thermoelectric device (i.e., the face of the thermoelectric device distal to the radiator; in other words, proximal to the frame). Temperature sensor for the inner face of the frame.

[0081] In these embodiments with sensors, the measurements obtained by the sensors can be taken into account in the regulation of the thermoelectric devices, the fans, and / or the thermovalve.

[0082] If the temperature of the room drops with respect to the setpoint temperature and the power dissipated by the radiator is insufficient (either because the capacity of the heat pump is insufficient or because the external temperature is too low), the thermoelectric devices will be activated with a voltage sufficient to increase the heat provided to the room. Moreover, the dissipation capacity of the radiator (with the casing) increases because the surface temperature of the outer casing increase. Moreover, the temperature of the water leaving the radiator is reduced. The lower the return temperature to the water circuit in the heat pump is, the better its performance will be.

[0083] In preferred embodiments, the processing and regulating unit is configured to activate the heat transfer fluid flow control module, the control module for the fans, and / or the power supply module for the thermoelectric devices based on the temperature of a heat transfer fluid entering the radiator through the fluid inlet.

[0084] In preferred embodiments, the thermal retrofitting system comprises: one or more environmental humidity sensors installed in the room where the radiator is located, configured to measure the relative humidity in said room.

[0085] In these embodiments, the control and regulating unit is configured to continuously monitor the relative humidity of the room through said one or more environmental humidity sensors. The humidity and temperature of air define its enthalpy. Using the humidity and temperature measurements of the air in preferred embodiments of the invention allows knowing the dew temperature, and therefore determining the temperature at which condensation occurs. This is important in the cooling mode of the invention given that the higher the humidity, the higher the dew temperature, and therefore the temperature of the outer metal plate (cooled by the thermoelectric devices) can be adapted based on the cooling and / or dehumidifying needs. One skilled in the art know how to determine the dew temperature in this context.

[0086] In preferred embodiments of the thermal retrofitting system comprising both the one or more ambient humidity sensors and the condensate tray, the processing and regulating unit is configured to activate the power supply module for the thermoelectric devices based on the relative humidity in the room and the amount of condensates in the condensate tray.

[0087] Advantageously, the claimed system can regulate condensation such that the relative humidity of the room, measured with the humidity sensors, is set at a predetermined value. In this way, dehumidification can be regulated. Likewise, the condensate tray can work as a humidifier in winter.

[0088] For example, in this embodiment: If the room is below the predetermined desired humidity value, the temperature of the thermoelectric devices is increased to favor the evaporation of the contents of the condensate tray. If the room is above the predetermined desired humidity value, the temperature of said thermoelectric devices will be lowered.

[0089] In preferred embodiments, the thermal retrofitting system comprises mechanical fastening means adapted to attach the frame to one of the thermoelectric devices and to the radiator, wherein said fastening means in turn comprise: a radiator anchoring and a frame anchoring surrounding the thermoelectric device; wherein the radiator anchoring is arranged on a first face of the thermoelectric device and the frame anchoring is arranged on a second face of the thermoelectric device opposite the first face; a screw going through the frame, the radiator anchoring, the frame anchoring, and at least one of the thermoelectric devices, one or more washers arranged at the ends of the screw.

[0090] In preferred embodiments, the radiator anchoring and / or the frame anchoring are metallic parts.

[0091] In more preferred embodiments, the washers are made of nylon.

[0092] In preferred embodiments, the fastening means further comprise a layer of thermal paste applied at the interface between each of the faces of the thermoelectric device and each of the parts.

[0093] In alternative embodiments not comprising mechanical fastening means, the thermal retrofitting system further comprises magnetic fastening means adapted to fix each of the thermoelectric devices between the frame and the radiator.

[0094] In preferred embodiments, the magnetic fastening means comprise two neodymium magnets arranged on the frame and the radiator, respectively, surrounding each of the thermoelectric devices.

[0095] In preferred embodiments of the invention, the frame is manufactured from a metallic material, preferably aluminum and / or galvanized metal plate.

[0096] In this way, the invention relates to a thermal retrofitting system comprising a casing suitable for installation thereof in a radiator. Said system, by means of a series of thermoelectric devices, pumps heat between the surface metal plate of the radiator and the environment, boosting the heating capacity of the radiator and / or providing it with cooling capacity.

[0097] The heating mode acts when the temperature of the water circulating through the radiator is not high enough for the temperature of a room where the radiator is installed to reach a preestablished temperature value. In this case, the thermoelectric devices installed between the surface metal plate of the radiator and the frame are activated. This increases the temperature of the frame, and therefore heats up the environment more at the expense of cooling the water in the radiator. This effect makes the water circuit, which supplies heat transfer fluid to the radiators, work at a lower temperature. Therefore, said water circuit can be heated using a thermal generator at a lower temperature, such as the case of a heat pump (an aerothermal system). In this way, it can replace the boilers which require a higher driving or operating temperature.

[0098] The lower the drive temperature of the heat pump is, the greater the performance thereof is generally. Moreover, the lower the temperature outside a building is, the lower the heating capacity of an aerothermal system is (therefore the lower the drive temperature is) such that the thermal retrofitting system of the invention acts as a back-up to complement the heating capacity of the aerothermal system in these cold conditions outside. In other words, the thermal retrofitting system acts as an additional heat generator to complement a reversible heat pump which provides the hot water that enters the radiator.

[0099] In preferred embodiments of the thermal retrofitting system of the invention, the heating mode operates as follows: The thermovalves limit the passage of the heat transfer fluid (water) when an area in the room where the radiator is located is not occupied or when it has been determined that said area will not be heated. The valves are configured to allow the passage of a flow rate of water ranging from at least about 300 l / h to at most 1000 l / h. When the temperature of the room is below a preestablished temperature to be reached (setpoint temperature), the heat pump turns on and water flows through the hydraulic circuit. In those rooms determined as being in use (either by detection or by scheduling), the thermovalves will open to allow the passage of the maximum flow rate (the thermovalve opening completely, as explained in the preceding point). If the heating ramp (i.e., the speed at which the temperature drops) of the room does not exceed a given threshold (for example, 0.5°C / h) then the fans are put into operation, going from a lower speed (for example, 400 revolutions per minute, rpm) to a higher speed (for example, 1500 rpm) with a PWM regulation system configured to increase their rotational speed by 450 rpm every 15 min if the heating ramp requirement of at least the preestablished threshold (for example, 0.5°C / h) is not met. In other words, if the room is not heated quickly enough with the operation of the thermovalves, then the fans are actuated in an auxiliary manner. If the heating ramp is insufficient even with the activation of the fans, then the thermoelectric devices turn on, regulating their supply voltage by means of a PID controller configured to reach the setpoint temperature of the room.

[0100] Moreover, the preferred embodiments of the thermal retrofitting system of the invention have a cooling mode. This way of cooling is activated when the temperature of the room in which the radiator is installed is higher than a preestablished temperature to be reached. In this case, cold water is circulated through the radiator, with the ability to boost the effect thereof by pumping heat between the casing and the surface metal plate of the radiator (in reverse compared to operation in the heating mode). In this case, the temperature of the frame of the invention is lowered at the expense of heating the water in the radiator. The water then circulates through the circuit of preexisting radiators in the room and returns to the generation unit, in this case, the heat pump. In this way, the radiator (which is originally use as a heater) is converted into a cold diffuser.

[0101] In more preferred embodiments, the cooling mode operates as follows: When cooling of a room is needed, a reversible heat pump is capable of cooling water, driving the fluid at a temperature lower than the temperature of the room (for example, 7°C) generally, and returning at a temperature higher than the previous temperature (for example, 12°C). The radiators themselves are not capable of suitably dissipating this cold (i.e., capturing heat from the environment). However, like in the heating mode, the thermostatic valves of the invention are configured to open the passage of water in those radiators located in the area where cooling is required. In the cooling mode, the fans are put into operation from the start and at the maximum range of revolutions (for example, 1500 rpm). If the device is not capable of absorbing the load for cooling the room (i.e., if the temperature does not go down despite the fans being activated), the thermoelectric devices are activated in a regulated manner by means of a PID controller.

[0102] In preferred embodiments, the thermal retrofitting system comprises a heat pump regulating module. In this way, the thermal retrofitting system can estimate the overall performance of the temperature control installation and, by knowing the number of rooms to be heated and the power required, the optimum water drive temperature (the lowest possible in principle) can be calculated, deciding to activate the frame only in the rooms where heating is required.

[0103] In a second inventive aspect, the invention provides a method for updating a radiator by means of using the thermal retrofitting system according to any of the embodiments of the first inventive aspect, wherein said method comprises performing the following steps: providing a radiator having a fluid inlet and a fluid outlet, said radiator being connected to a reversible heat pump; and fixing, using the fastening means, the thermal retrofitting system to the radiator; such that the radiator and the thermoelectric devices are in thermal contact; and configuring said thermovalve to provide values of the flow rate of the heat transfer fluid entering the radiator of between 300 and 1000 l / hour.

[0104] In preferred embodiments, the method further comprises: configuring the control module for the fans configured to establish an range of revolutions of said fans of between 400 and 1500 rpm.

[0105] In preferred embodiments, the method further comprises: configuring the power supply module for the thermoelectric devices configured to provide a supply voltage of the thermoelectric devices of between 0 and 12 V.

[0106] As a result of the control module for the fans, temperature can be regulated through the indirect regulation of the coefficient of convection. The natural coefficient of convection is in a range of 2-20 W / m 2< K. This coefficient is raised to 25-300 W / m 2< K using forced convection by means of the control module for the fans, based on the speed of the fans.

[0107] To summarize the invention: The invention uses the thermoelectric devices both for heating and for cooling and / or dehumidifying interior spaces. The invention is designed to be integrated with an existing radiator. The invention allows providing greater functionality to a conventional radiator, going from being a mere heat dissipator with power given by the temperature of the water reaching it through the pipes of the building where it is installed to being an element with a certain degree of autonomy, which allows heating, cooling (which is not possible with a conventional radiator), and even dehumidification. The invention allows the receiving radiators to work with a high heat emission when combined with a heat pump, such that said heat pump provides hot water to the radiator, entering the radiator through the water circuit. The heat pump operates with a driving temperature (40-45°C) that is lower than the boiler (about 70-75°C).

[0108] The solution proposed in the present invention presents several benefits: Reduction of environmental impact derived from the reduction of scraps (about 80 kg of aluminum per dwelling, equivalent to 1.2 tons of CO 2 ) and debris from the corresponding work. Expansion of the common heating functionality of the radiator to provide temperature control, i.e., making it possible to furthermore cool and dehumidify the retrofitted spaces, a key aspect in the future. Improvement in thermal comfort and possibility of regulating the new temperature control system. The heat pumping capacity at the radiator level allows a distributed temperature control, while at the same time optimizing the overall efficiency of the temperature control installation in the building. Compensation for temperature control limitations in an aerothermal system by increasing heating power by 20% when the external temperature drops significantly. Reduction of installation times with respect to other temperature control alternatives (75% savings in installation time with respect to the installation of fan coils and 93% with respect to underfloor heating). Reduction of economic costs, with an estimated savings of about 50% with respect to the installation of new fan coils and 66% with respect to underfloor heating.

[0109] All the features of the system and / or the steps of the methods described in this specification (including the claims, description, and drawings) can be combined in any combination, with the exception of the combinations of such mutually exclusive features.DESCRIPTION OF THE DRAWINGS

[0110] These and other features and advantages of the invention will be more apparent based on the following detailed description of a preferred embodiment given only by way of illustrative and non-limiting example in reference to the attached figures. Figure 1 shows an exploded view of a conventional radiator to which an embodiment of the thermal retrofitting system of the invention has been incorporated. Figure 2 corresponds to a top view of the frame of an embodiment of the thermal retrofitting system of the invention, once installed on the radiator. Figure 3a) shows a side view of an embodiment of the thermal retrofitting system of the invention, once installed on the radiator. Figure 3b) illustrates an enlarged view of the mechanical fastening system used in this embodiment of Figure 3a). Figure 4 depicts a preferred embodiment of the thermal retrofitting system of the invention, which is connected to several additional control modules to regulate the water flow entering and exiting the radiator, as well as to control the operation of the fans (thereby regulating the coefficient of convection) and to supply power to the thermoelectric devices. Figures 5-8 depict the different steps of an embodiment of the method for updating a radiator according to the present invention, which comprises the use of the retrofitting system to expand the functionality of the radiator. In particular: Figure 5 depicts the first step of the method, where the step starts from a pre-existing radiator. Figure 6 illustrates how thermoelectric devices are incorporated in the radiator. Figure 7 shows how the frame is fixed on the radiator. Figure 8 corresponds with the installation of the thermovalve in the fluid inlet of the radiator.

[0111] The table below lists all the reference numbers that appear in the preceding figures: ReferenceElement1Radiator1.1Metal plate of the radiator2Fans3Thermovalve or thermostatic valve4Frame or casing4.1Slots in the front portion of the frame4.2Holes in the upper portion of the frame5Thermoelectric device6Fastening means6.1First part or radiator anchoring6.2Second part or frame anchoring / casing6.3Screws6.4Insulating thermal paste6.3.1, 6.3.2Washers7Condensate collection tray8Heat transfer fluid (e.g., water) flow control module8.1Fluid inlet in the radiator8.2Fluid outlet of the radiator9Control module for the fans (to control the coefficient of convection)10Power supply module for the thermoelectric devices11Processing and regulating unit DETAILED DESCRIPTION OF THE INVENTION Embodiments of the thermal retrofitting system

[0112] Some embodiments of the invention illustrated in Figures 1 to 8 will be explained in greater detail in this section. Furthermore, it shall be assumed that the thermal retrofitting system (100) of the invention is installed in a conventional radiator (1) arranged in a room of a building, which has a water circuit providing a fluid that enters the radiator (1).

[0113] As shown in Figure 1, the thermal retrofitting system (100) of the invention is adapted for installation in a radiator (1), such that it expands the functionality of said radiator. The radiator (1) comprises a metal plate (1.1), a fluid inlet (8.1), and a fluid outlet (8.2). The radiator (1) receives water from the water circuit of the building through the fluid inlet (8.1), while the fluid is returned to the water circuit through the fluid outlet (8.2).

[0114] The thermal retrofitting system (100) comprises a frame (4) and one or more thermoelectric devices (5) that are powered with a specific voltage and can work in two different modes: heating mode (in which heat is pumped between the radiator (1) and the frame (4) of the invention) and cooling mode. In the heating mode, the temperature of a front casing (4.1) of the frame (4) is raised and the water in the radiator (1) is cooled. The opposite happens in the cooling mode.

[0115] As can be seen, the frame (4) comprises a plurality of slots (4.1) in the front portion, as well as a plurality of holes (4.2) in the upper portion thereof. These holes (4.2) are illustrated in greater detail in the top view of the frame (4) of Figure 2. Furthermore, the embodiment of the thermal retrofitting system (1) of Figure 1 comprises: fans (2) arranged in the frame (4) and configured to increase the coefficient of convection, favoring heat exchange between a casing (4.1) of the frame (4) and the environment; and a thermovalve (3) arranged in the fluid inlet (8.1) of the radiator configured to regulate the flow rate of the water passing through the radiator.

[0116] In Figure 3a), the fans (2) are arranged in the upper portion of the frame (4), although this location is not essential. In other embodiments of the thermal retrofitting system (100), the fans (2) are arranged in the casing (4.1) of the frame (4), as illustrated in the embodiment of Figure 4.

[0117] Moreover, the thermal retrofitting system (100) comprises fastening means (6) configured to provide a good thermal contact between the radiator (1) and the thermoelectric devices (5). Likewise, the fastening means (6) are adapted to allow the diffusion of heat, for example, being manufactured with a thermal conductive material (for example, galvanized metal plate, aluminum, or another metal).

[0118] In the field of the present invention, a good thermal contact shall be understood to mean contact which preferably has a thermal resistance less than or equal to 4 × 10 − 4 m 2 K W , which is equivalent to 1 mm of thermal paste and 2 cm of steel. In general, a layer of thermal paste that is as thin as possible, preferably with a thickness not exceeding 1 mm, is suitably used in the invention. In this way, the thermal conductivity of the paste material is not as critical as a homogenous distribution of the paste between the surfaces to be thermally coupled of the invention.

[0119] An example of these fastening means (6) is illustrated in Figure 3a) in which two mechanical fastening means (6) can be seen. Each of these fastening means (6) comprises a first part or radiator anchoring (6.1) and a second part or frame anchoring (6.2) which are coupled to the frame (4) and surround the thermoelectric devices (5) like a sandwich. The parts (6.1, 6.2) are fastened to the thermoelectric devices (5) by mechanical fastening means, particularly screws (6.3) and washers (6.3.1, 6.3.2), as can be seen in the enlarged view of Figure 3b). In this example, first washers (6.3.1) can be found in the interface between the metal plate (1.1) of the radiator (1) and the first part or frame anchoring (6.1), while second washers (6.3.2) can be found in the interface between the second part or frame anchoring (6.2) and the frame (4). In other words, the thermoelectric devices (5) are fixed between the first part or radiator anchoring (6.1) and the second part or frame anchoring (6.2) on the inside of the frame (4). The first washers (6.3.1) are proximal with respect to the radiator (1), while the second washers (6.3.2) are proximal with respect to the frame (4) (i.e., distal with respect to the radiator (1)).

[0120] In preferred embodiments, the washers (6.3.1, 6.3.2) attaching the radiator anchoring (6.1) and the frame anchoring (6.2) are made of nylon to facilitate thermal bridge breakage.

[0121] In the embodiment of Figure 3b), it can be seen how the radiator anchoring (6.1) is arranged between the metal plate (1.1) of the radiator (1) and the thermoelectric device (5). In this way, the fastening means (6) are adapted to allow thermal contact between the radiator (1) and the thermoelectric devices (5).

[0122] In preferred embodiments, a thermal paste (6.4) is used to improve the thermal coupling between the radiator (1) and the thermoelectric devices (5). More preferably, the thermal paste (6.4) has a silicone-, ceramic-, or metal-based composition. In certain embodiments, the thermal paste (6.4) is filled with high thermal-conductivity metals (for example, silver, aluminum, gold, or alloys thereof), metal oxides (of zinc or aluminum), or boron nitrite.

[0123] In preferred embodiments, a layer of thermal paste (6.4) with a thickness less than or equal to 1 mm is used. In even more preferred embodiments, the layer of thermal paste (6.4) has a substantially uniform thickness and is homogenous (i.e., preventing air bubbles from being trapped therein). Advantageously, thermal coupling is superior when the thermal paste is homogenously distributed. To that end, tightening of the elements of the invention that are thermally coupled through the thermal paste must be uniform and sufficient to ensure that the layer of thermal paste is as thin and as uniform as possible.

[0124] The frame (4) is adapted to dissipate heat to the environment in the heating mode, while it is adapted to cool the environment in the cooling mode. To that end, the power supply received by the thermoelectric devices (5) is adapted, as will be explained below.

[0125] As can be seen in the embodiment of Figure 3a), there is arranged at the bottom of the frame (4) a condensate collection tray (7) which is useful when working in the cooling mode. In the case of working in the cold mode, the casing or frame (4) may cause condensation of water that would be collected in the lower portion of the radiator (1).

[0126] The final performance of the invention greatly depends on achieving a good thermal contact between the thermoelectric devices (5) and the radiator (1), as well as between the thermoelectric devices (5) and the frame (4). If the parts (6.1, 6.2) that put the thermoelectric devices (5) in contact with the frame (4) or the radiator (1) are poorly machined, or if thermal paste (6.4) is absent, elevated thermal resistances may be produced, which can cause a 10% drop in overall system performance (i.e., heat emission capacity). To prevent same, preferred embodiments of the invention (such as that illustrated in Figure 3) proposes the following: Fastening the thermoelectric device (5) to the radiator (1) by means of a radiator anchoring (6.1) manufactured from a metallic material, wherein said radiator anchoring (6.1) is located behind the visible outer metal plate (1.1) of the radiator (1). Then, a metallic frame anchoring (6.2) is placed which, together with the radiator anchoring (6.1), surround the thermoelectric device (5) like a sandwich. The two metallic parts are separated by an insulating material. A conductive thermal paste (6.4) is applied between the metallic anchorings (6.1, 6.2) and the thermoelectric device (5) to ensure a good thermal contact. Finally, two screws (6.3) or bolts go through the two parts (6.1, 6.2), with the outer metal plate (1.1) of the radiator (1) being arranged between them. The screws (6.3) are supported on the radiator anchoring (6.1) and on the frame anchoring (6.2) with nylon washers to reduce the thermal bridge between said anchorings (6.1, 6.2). Preferably, tightening applied by means of screws (6.3) and washers (6.3.1) for the attachment of the radiator anchoring (6.1) and the metal plate (1.1) must be at least 5 Nm. Also preferably, said tightening is uniform in said attachment. The frame (4) is anchored to the frame anchoring (6.2) by means of screws (6.3) and washers (6.3.2) directly (given that, in this case, thermal bridge breakage is not necessary) with tightening of at least 4 Nm.

[0127] In preferred embodiments, the frame (4) is made of a metallic material, preferably aluminum and / or galvanized metal plate. Advantageously, this favors the dissipation of heat from one of the outer faces of the thermoelectric devices (5) to the room environment. This heat dissipation effect can be reinforced as a result of the fans (2) in those embodiments of the invention comprising same.

[0128] It should be highlighted that although the fastening means (6) of Figure 3 are of mechanical origin, in other embodiments of the thermal retrofitting system (100), the fastening means can be magnetic means.

[0129] Figure 4 shows another embodiment of the thermal retrofitting system (100) of the invention, showing the details of the control modules involved in the system. In particular, the thermal retrofitting system (100) comprises: a heat transfer fluid flow control module (8) which is configured to operate the thermovalve (3) and to set the flow rate of water entering the radiator (1). a control module (9) for the fans (2), which is configured to regulate the range of revolutions of said fans (2), thereby regulating the coefficient of convection of the thermal retrofitting system (100) and favoring heat exchange between the frame (4), the radiator (1), and the environment of the room. a power supply module (10) for the thermoelectric devices (5), which is configured to set the operating voltage of the thermoelectric devices (5) based on room temperature of the room where the thermal retrofitting system (100) and the radiator (1) are located, as well as on the target temperature. For example, the power supply module (10) comprises a battery providing direct current. In a preferred embodiment, the power supply module (10) is regulated with a PID controller with settings that can be regulated for the proportional, integral, and derivative components.

[0130] In this preferred embodiment, the modules (8, 9, 10) are connected to and regulated in a centralized manner by a processing and regulating unit (11) which acts as a control unit that automatically establishes the values of the control parameters that said modules (8, 9, 10) subsequently apply on the fans (2), the thermovalve (3), and the thermoelectric devices (5). In other words, the processing and regulating unit (11) supplies electric power to the thermoelectric devices (5), the fans (2), and / or the thermovalve (3); and based on temperature control needs of the room and on the temperature of the water entering the radiator (1), said processing and regulating unit (11) is configured to establish the supply voltage of the thermoelectric devices (5), the supply voltage of the fans (2), and the passage flow rate of the thermostatic valve (3).

[0131] Likewise, the processing and regulating unit (11) is communicated with a reversible heat pump (not depicted in the figures). This heat pump is responsible for providing hot water to the fluid inlet (8.1) of the radiator. In even more preferred embodiments, the communication between the processing and regulating unit (11) with the heat pump is wireless.

[0132] In a preferred embodiment, the thermal retrofitting system (100) comprises presence sensors configured to automatically activate the system when they detect people in the room where the radiator (1) having said thermal retrofitting system (100) is located. Advantageously, this allows greater energy savings since the system only begins operation when the room is occupied.

[0133] In a preferred embodiment, the thermal retrofitting system (100) comprises an occupation prediction module which comprises one or more presence sensors and is connected to the processing and regulating unit (11). In this embodiment, the presence sensors are configured to collect measurements relating to presence in and occupation of the room, and then send the measurements to the processing and regulating unit (11), where said measurements are processed to estimate occupation trends.

[0134] In a preferred embodiment, the thermal retrofitting system (100) comprises temperature and / or humidity sensors configured to send temperature and / or humidity measurements of the room where the radiator (1) with said thermal retrofitting system (100) is located to the processing and regulating unit (11). Once the processing and regulating unit (11) received the parameters measured with the sensors, it sends the necessary settings to the modules (8, 9, 10).

[0135] In a preferred embodiment, the fastening means (6) are magnetic means placed directly on the radiator (1). In even more preferred embodiments, the fastening means (6) comprise neodymium magnets arranged directly on the frame (4) and adapted to exert a sufficient force to secure said frame (4) and a frame anchoring (6.2) to one another. In this embodiment, and unlike the embodiment of Figure 3, the radiator anchoring (6.1), the screws (6.3), and the washers (6.3.1, 6.3.2) are not necessary.

[0136] In another alternative embodiment, the anchoring system is a mechanical system (such as, for example, the system of Figure 3) and ensures a good thermal contact.

[0137] The fans (2) of some embodiments of the invention allow setting the coefficient of convection between the frame (4) and the air of the room. In this way, the joint regulation of the thermoelectric devices and the fans enhances the use thereof in both the heating mode and the cooling mode.

[0138] As a result of the condensate collection tray (7), the thermal retrofitting system of the invention is capable of acting as a dehumidifier with additional regulation capacity as a result of the installation of the thermoelectric devices (5).

[0139] The design of the frame (4) ensures a good heat exchange between the thermoelectric devices (5) and the environment of the room where the radiator (1) with the thermal retrofitting system (100) is installed. Advantageously, this frame (4) may have other additional uses such as being used as a drier for clothes or a heat retainer for a cup of coffee.

[0140] In preferred embodiments, the frame (4) also comprises thermoelectric devices (5). In these embodiments, the thermoelectric devices (5) are not fastened to the fastening means (6), but directly integrated in the frame (4). In this way, in these embodiments the frame (4) is an add-on which can be attached directly to the radiator (1) in a manner that can be decoupled from same.

[0141] In preferred embodiments, the thermal retrofitting system is adapted to control multiples radiators (1) installed in different rooms of the same building. In these embodiments, a single control and regulating unit (11) is configured to regulate the thermoelectric devices (5) and, where appropriate, the thermovalves (3) and the fans (2) of each of the radiators (1). Therefore, an adaptation of the temperature control of each room can be performed individually, boosting the capacity to heat and / or cool each room based on the actual needs of each of them.

[0142] In other embodiments, the thermal retrofitting system (100) can be communicated with the aerothermal heat pump or the heat generator of the building.

[0143] Throughout this description, water was considered the fluid of the radiator. However, the thermal retrofitting system of the invention works regardless of which heat transfer fluid is used.Example of the operation of an embodiment of the invention in the heating mode

[0144] The operation of an embodiment of the thermal retrofitting system (100) of the present invention, which is installed in a radiator (1), is set forth below. In turn, said radiator (1) is connected to a reversible heat pump through pre-existing installation.

[0145] For this example it shall be assumed that the room is at a first temperature (for example 15°C) and that the setpoint temperature to be reached is a second temperature, higher than the first temperature (e.g., 21°C). The setpoint temperature can be indicated, for example, through a thermostat.

[0146] Likewise, it shall be assumed that the room the temperature of which is to be controlled comprises a single radiator (1) in which the thermal retrofitting system (100) of the invention, comprising the thermovalve (3), as well as fans (2) and thermoelectric devices (5), has been installed.

[0147] In this case it shall be assumed that a presence sensor of the invention for detecting the presence of people is present, such that the occupation of the room can be detected. When it is determined that there are people in the room, the following operation of the thermal retrofitting system (100) takes place in order to heat said room and to reach the second temperature (setpoint temperature): 1) The thermovalve (3) is set to open (at least partially) the heat transfer fluid inlet (8.1) based on the difference between the temperature of the heat transfer fluid and the setpoint temperature. In some embodiments, when the temperature of the heat transfer fluid is too low (for example, at a third temperature, preferably below 40°C), then the thermovalve (3) allows all the heat transfer fluid to pass to the radiator. 2) Actuating the fans (2): If the temperature of the room does not change towards the setpoint temperature only by means of the preceding step after a first preestablished time (for example, 1-2 minutes), then the fans (2) are activated at a certain number of revolutions per minute (for example, 400 rpm), and said speed is gradually increased to a higher speed (for example, 1000 rpm). This last speed should not be the maximum speed allowed by the fan (2), so as to ensure a silent operation. 3) Actuating the thermoelectric devices (5) when the temperature of the room does not reach the setpoint temperature in a second preestablished time (for example, greater than the first preestablished time, assuming another 1-2 minutes) once the preceding steps 1 and 2 have taken place. This can occur either because the external temperature is too low, and therefore there are excessive losses in the heat pump to which the radiator is connected, or because the power of the radiator (1) is insufficient, due to a low temperature of the heat transfer fluid. In this case, the thermoelectric devices (5) must be activated by setting the supply voltage (for example, between 0 and 12 V).

[0148] In this way, the thermoelectric devices (5) heat the frame (4), raising its temperature above the temperature of the heat transfer fluid. This allows adding heat emission to the radiator (1), increasing the heat exchange efficiency of the thermal retrofitting system (100) in the room, furthermore favored by the fans (2).

[0149] The heat transfer fluid reaching the fluid inlet (8.1) of the radiator (1) at the third temperature (40°C) will experience a drop in temperature due, firstly, to the heat being given off to the environment through the surface of the radiator favored by the fans, and secondly, to the thermoelectric devices (5). The inner face of these thermoelectric devices (5), in thermal contact with the radiator (1), will cool down, which causes a reduction in the temperature of the heat transfer fluid circulating therein. The higher the voltage applied is, the greater this cooling will be.

[0150] The fluid exits the radiator (1) through a fluid outlet (8.2) colder than when it was introduced (for example, at a fourth temperature of between 35 and 39°C) and is heated again in the reversible heat pump to which the radiator (1) is connected.Example of the operation of an embodiment of the invention in the cooling mode

[0151] A different example, where the room temperature of the room is a first temperature (for example, 29°C) that is higher than a second temperature (or setpoint temperature, for example, 24°C), will be considered below. It shall also be assumed that the thermal retrofitting system (100) has a presence sensor that allows initiating regulation when it detects that the room is occupied.

[0152] Likewise, it shall be assumed that the room the temperature of which is to be controlled comprises a single radiator (1) in which the thermal retrofitting system (100) of the invention, which comprises the thermovalve (3), as well as fans (2) and thermoelectric devices (5), has been installed. Said radiator (1) will be connected to a heat pump acting in the cooling mode.

[0153] When it is determined that there are people in the room, the following operation of the thermal retrofitting system (100) takes place in order to cool said room and to reach the second temperature (setpoint temperature): 1) The thermovalve (3) is set to open (at least partially) the heat transfer fluid inlet (8.1) based on the difference between the temperature of the heat transfer fluid and the setpoint temperature. In some embodiments, when the temperature of the heat transfer fluid is relatively high (for example, at a fifth temperature, preferably above 18°C), then the thermovalve (3) allows all the heat transfer fluid to pass to the radiator (1). 2) Actuating the fans (2): If the temperature of the room does not change towards the setpoint temperature only by means of the preceding step after a first preestablished time (for example, 1-2 minutes), then the fans (2) are activated a at a certain number of revolutions per minute (for example, 400 rpm), and said speed is gradually increased to a higher speed (for example, 1000 rpm). This last speed should not be the maximum speed allowed by the fan (2), so as to ensure a silent operation. 3) Actuating the thermoelectric devices (5) when the temperature of the room does not drop to the setpoint temperature in a second preestablished time (for example, greater than the first preestablished time, assuming another 1-2 minutes) once the preceding steps 1 and 2 have taken place. This can occur either because the external temperature is too high and, therefore, there is an additional cooling need; or because the cooling capacity of the heat pump is insufficient).

[0154] In this way, the thermoelectric devices (5) cool the frame (4), lowering its temperature below the temperature of the heat transfer fluid. This allows boosting the heat exchange of the assembly of radiator (1) and thermal retrofitting system (100) in the room, favored by the fans (2). Additionally, when the surface temperature thereof is below the dew temperature of the room (for 26°C and 50% relative humidity, the dew temperature would be 14.8°C), condensation will occur in the frame (4), where it can be collected and discharged through the lower portion of the frame since a condensate collection tray (7) is installed, contributing to a reduction in the latent cooling load.

[0155] The heat transfer fluid will experience an increase in temperature due, firstly, to the absorption of heat from the environment through the surface of the radiator (1) favored by the fans (2,) and secondly, to the thermoelectric devices (5) the inner face of which, in thermal contact with the radiator (1), will heat up, which causes an increase in the temperature of the heat transfer fluid circulating therein. The higher the voltage applied is, the greater this heating will be.

[0156] Conventional cold generators (for example, air-conditioning apparatus) do not distribute their temperature control capacity through radiators (1), but rather cool the air of the room directly or using fan coils. In contrast, in the present invention the fluid exits the radiator (1) through the fluid outlet (8.2) hotter than when it was introduced and is cooled again in the heat pump to which said radiator is connected. Therefore, the thermal retrofitting system (100) is configured to add this cooling capacity to a radiator (1) by adding the effect of the fans (2) on one hand and allowing the cooling capacity by means of the thermoelectric devices (5) to be increased, reducing the temperature of the frame (4), on the other hand. In other words, the invention allows distributing the temperature control capacity of the heat pump through radiators.Embodiments of the method for the installation of the thermal retrofitting system of the invention in a pre-existing radiator

[0157] Part of the invention also relates to a method for the installation of the thermal retrofitting system (100) according to the first inventive aspect, which allows updating and expanding the functions of a pre-existing conventional radiator. This method is illustrated in Figures 5 to 8 and comprises the following steps: Step 1 (see Figure 5): Providing a radiator (1). For example, this radiator (1) can be a conventional radiator already installed in the building and usually connected to the water circuit. Step 2 (see Figure 6). Placing one or more thermoelectric devices (5) on the radiator (1) using fastening means or anchoring (6) that will be fastened to the radiator (1). For example, they can be placed on the casing (1.1) of said radiator (1), in thermal contact with same. For the sake of simplicity, the fastening means or anchoring (6) have not been depicted in Figure 6, but in this preferred embodiment said system is that of Figure 3. The fastening means (6) perform two functions: on one hand, ensuring a good thermal contact between the radiator (1) and the thermoelectric devices (5); and, on the other hand, securing the frame (4) of the thermal retrofitting system (100), which is then installed in the following step. Step 3 (see Figure 7). Installing the frame (4), which is anchored to the radiator (1) and the thermoelectric devices (5) through the fixing system or anchoring (6).

[0158] In a preferred embodiment, the method for installation optionally comprises the following step: Step 4 (see Figure 8). Installing the thermovalve or thermostatic valve (3) in the fluid inlet (8.1) in the radiator (1) next to the water stopcock at the inlet of the radiator (1). This thermovalve (3) regulates the flow rate of water entering the radiator (1) and allows setting same based on the temperature control needs of the room and the external environmental conditions.

Examples

Embodiment Construction

Embodiments of the thermal retrofitting system

[0112]Some embodiments of the invention illustrated in Figures 1 to 8 will be explained in greater detail in this section. Furthermore, it shall be assumed that the thermal retrofitting system (100) of the invention is installed in a conventional radiator (1) arranged in a room of a building, which has a water circuit providing a fluid that enters the radiator (1).

[0113]As shown in Figure 1, the thermal retrofitting system (100) of the invention is adapted for installation in a radiator (1), such that it expands the functionality of said radiator. The radiator (1) comprises a metal plate (1.1), a fluid inlet (8.1), and a fluid outlet (8.2). The radiator (1) receives water from the water circuit of the building through the fluid inlet (8.1), while the fluid is returned to the water circuit through the fluid outlet (8.2).

[0114]The thermal retrofitting system (100) comprises a frame (4) and one or more thermoelectric devices (5) that are po...

OBJECT OF THE INVENTION

[0001] The present invention relates to a thermal retrofitting system for a radiator, applicable for updating said radiator such that it has heating and cooling capacity; as well as to a method for updating a radiator by means of the installation of said system. The invention can be intended for the thermal retrofitting of interior spaces of buildings, allowing the water circuit and radiators existing previously in said buildings to be maintained.BACKGROUND OF THE INVENTION

[0002] Construction context will change significantly in the coming years: new buildings are built to high efficiency standards and many resources are being mobilized to retrofit the thermal envelope of existing buildings. As a consequence, buildings will need less heating and more cooling, due to climate change and increased demand for comfort. Moreover, decarbonization means that existing fossil fuel boilers will no longer be installed and replaced, which encourages the installation of heat pumps in buildings.

[0003] Retrofitting work with improved thermal envelope can considerably reduce (by 30-40%) the demand for heating power, but this reduction is not the same in all spaces of a building. Moreover, an improved envelope may mean an increase in the need for cooling, which increases with climate change.

[0004] In view of the foregoing, it is necessary to provide alternatives that allow thermally retrofitting the interior spaces of buildings and dwellings, without the need to replace the water circuits and radiators already installed therein. Old buildings usually have a boiler that provides hot water to the radiator.

[0005] Heat pumps, which represent an alternative for replacing a boiler, for providing hot water to a radiator, are known in the state of the art. In this sense, the hot water in gas boilers is generally driven to the radiators at 70-75°C. Heat emission from the radiators greatly depends on this high temperature, such that their heat emission decreases considerably if this hot water driving temperature is lowered to a more moderate range (40-45°C).

[0006] Heat emission from the radiator depends on the temperature difference between the radiator (its average temperature) and the environment. If the temperature at which the fluid enters the radiator is expressed as t e , the temperature at which the fluid exits the radiator as t s , t m is the mean temperature of said radiator and is calculated as t m = t e + t s 2 , with t a being at room temperature, the heat emission (Q) of the radiator is given by the expression: Q = Q 50 ⋅ Δ T 50 n , where ΔT = t m - t a is the rise in temperature between the radiator and the environment, Q50 is the heat emission corresponding to normal conditions (to a rise in temperature of 50°C), and "n" is the exponent that depends on the geometry of the radiator (usually n=1.3). In general, the heat transfer fluid is water, such that in the following reference will be made exclusively to water as said fluid.

[0007] The thermal power that a radiator is capable of dissipating depends on the mass flow, but, above all, on the temperature reached by the heat transfer fluid, usually water.

[0008] The heat output that the radiator is capable of dissipating depends on the rise in temperature between the room environment (usually 20°C) and the mean temperature of the outer metal plate of the radiator.

[0009] For example, if the temperature of the water reaching the radiator decreases from 75°C to 40°C, for an environment at a temperature of 20°C, then heat emission from the radiator can be reduced by about 70%. In other words, if the boiler is changed for a heat pump, the temperature reached in the driving operation is generally lower. Surprisingly, some boiler pumps can reach 70°C, but with very poor performance.

[0010] The temperature at which a heat pump works with good performance is about 40°C. If the drive temperature (the one that reaches the radiator) goes from 75 to 40°C, the thermal power that the radiator is capable of dissipating is one third of what was originally intended.

[0011] Therefore, replacing boilers with heat pumps to provide hot water to radiators is not without problems, particularly, the reduction of heat emission. Furthermore, this replacement does not allow providing the radiator with cooling capacity.

[0012] Some of the major drawbacks of replacing boilers with aerothermal installations (i.e., using heat pumps) are as follows: i. if the intention is to keep the radiators, the performance of the equipment is very low, significantly increasing the electrical cost; ii. if the intention is to take advantage of the opportunity for cooling, it is necessary to change the radiators for fan coils or underfloor heating or cooling, which increases installation costs and time, in addition to causing greater environmental impact; and iii. when the external temperature drops (which is precisely when the use of heating is most needed), the heating capacity of the aerothermal system decreases, causing situations of thermal discomfort. In particular, when the external temperature drops, the temperature of the heat transfer fluid that will reach the radiator will be insufficient, as the aerothermal system will work worse.

[0013] In the case of replacing the heat boiler with a heat pump, it is possible to opt for vapor compression cycles at 70°C or for systems installed in the radiators themselves, referred to as boosters for said radiators. An example of these boosters is shown in document WO 2018 / 229314 A1, which allows increasing the convection and heat dissipation capacity of the radiator.

[0014] Boosters generally incorporate direct current fans that are intended to add a fan coil effect to the radiator, such that they can partially compensate for a lower water driving temperature. However, these boosters do not allow cooling, which makes it necessary to incorporate an additional AIR-AIR air conditioning system, increasing the impact of building retrofitting, both environmentally and visually on the façade. As is known in this technical field, an AIR-AIR air conditioning refers to the fact that the external unit is air (if it is air, it is a heat exchanger on the façade with the outside air; if it is water, it would be a geothermal system), and that the internal unit where it delivers the cold or heat is also air (therefore, an internal air unit would be a conventional air conditioning, while an internal water unit would be a water circuit with fan coils).

[0015] Alternatively, it is also possible to opt for a reversible heat pump (i.e., adding the cooling option). However, this alternative requires the incorporation of low-temperature emitters (underfloor heating and / or fan coils).

[0016] The invention provides a thermal retrofitting system which allows combining conventional radiators with heat pumps, additionally providing cooling capacity to said radiators and improving thermal efficiency.DESCRIPTION OF THE INVENTION

[0017] The present invention allows overcoming the limitations of the state of the art identified above by means of a thermal retrofitting system according to claim 1. The dependent claims define preferred embodiments of the invention.

[0018] In a first inventive aspect, the invention relates to a thermal retrofitting system for a radiator located in a room at room temperature, wherein the radiator is connected to a reversible heat pump, wherein the thermal retrofitting system comprises: a frame adapted to be coupled to the radiator; and one or more thermoelectric devices configured to be housed in said frame, wherein each of the one or more thermoelectric devices comprise two faces: ∘ a first face configured to be in thermal contact with the radiator, said first face being proximal to the radiator; and ∘ a second face, opposite the first face, which is configured to be in thermal contact with the frame, said second face being proximal to the frame; and one or more fans configured to be housed in the frame; a thermovalve adapted to be arranged in a fluid inlet of the radiator; a heat transfer fluid flow control module configured to operate the thermovalve and to set the flow rate of heat transfer fluid entering through the fluid inlet of the radiator; a processing and regulating unit configured to communicate with the reversible heat pump and with the heat transfer fluid flow control module; wherein the processing and regulating unit is configured to activate the reversible heat pump in a heating mode when the room temperature of the room is lower than a setpoint temperature to be reached and to activate the heat transfer fluid flow control module, and said heat transfer fluid flow control module is configured to open the thermovalve completely and to set the maximum flow rate of water available in the radiator as long as the setpoint temperature is not reached.

[0019] The thermal retrofitting system of the invention is useful in retrofitting the interior spaces of buildings and dwellings, when the heating and cooling systems thereof are to be updated without having to remove old radiators or make modifications to the water circuit available in the building. In the field of the invention, thermal retrofitting shall be understood as the conditioning and improvement of the functionality of a radiator.

[0020] In particular, the invention facilitates the replacement of gas boilers in buildings or dwellings with reversible heat pumps, preserving the water circuit and the radiators themselves which are already installed in said buildings or dwellings.

[0021] Moreover, heat pumps require a maximum temperature of about 40-45°C and they lose efficiency beyond said temperature. Therefore, directly replacing the gas boilers of the buildings with heat pumps is not an optimal solution since the maximum temperature of the heat pumps is insufficient for conventional radiators to perform suitably.

[0022] In this way, a first technical problem solved by the present invention is how to couple a heat pump to a conventional radiator as an alternative to a pre-existing boiler. In other words, the invention allows avoiding the problems of a poor heat emission that would result from the combination of a conventional radiator and a heat pump, allowing the heat pump to be an effective option in the retrofitting of buildings where the radiators and the water circuit are to be preserved.

[0023] Moreover, the invention solves a second technical problem: how to adapt a conventional radiator for cooling. Advantageously, this allows improving thermal comfort in the interior spaces of buildings without replacing said radiators, thereby avoiding the higher economical cost and execution time for retrofitting that would be entailed by opting for the installation of underfloor heating or fan coils.

[0024] It should be highlighted that the present invention solves both technical problems mentioned above simultaneously.

[0025] The thermal retrofitting system of the invention has two operating modes: a heating mode and a cooling mode, that will depend on whether the reversible heat pump is operating in the heating or cooling mode. In the invention, it shall be understood that the pump operates in the heating mode when the setpoint temperature to be reached in the room is higher than room temperature, and in the cooling mode when the setpoint temperature to be reached in the room is lower than room temperature. In both cases, the thermal retrofitting system acts by boosting the heating or cooling provided by the reversible heat pump, in order to shorten the time to reach said setpoint temperature.

[0026] Therefore, in the present invention, the thermoelectric devices are used to raise the drive temperature without the heat pump having to work at a higher temperature. The invention allows compensating for the decrease in heat emission when the boiler is to be replaced with a heat pump to work together with conventional radiators.

[0027] A differential element with respect to the state of the art is the use of thermoelectric devices to serve as a support when the temperature of the water reaching the radiator is insufficient to provide the power that it needs to generate the necessary heat emission that arises the temperature of the room to a setpoint temperature.

[0028] In this way, the invention allows regulating the heat pump in the best way possible, performing a different regulation in each room based on needs, and boosting heat production if the production system does not allow same (in the case of an aerothermal heat pump and extreme external temperatures). Moreover, it allows the radiator to work in the cooling mode and even as a dehumidifier, a use that is not originally intended for the radiators.

[0029] The invention comprises a frame which is installed on the existing radiator. There are housed in the frame one or more thermoelectric devices having two faces or surfaces: with one face providing cooling and another face providing heating. The thermoelectric devices pump heat between their two faces, such that, in the heat mode, when the radiator is circulating low-temperature water (for example, 40°C), the thermoelectric device will raise the temperature of its hot side (in contact with the metal plate covering the radiator, and which is exposed) to 70°C, delivering more heating power which will be regulated in a very precise manner by means of the supply voltage of the thermoelectric devices.

[0030] When the boiler is replaced with a heat pump, the thermal retrofitting system can work in the heating mode and in the cooling mode. However, the problem arises from the mere replacement of the boiler with the heat pump is as follows: On one hand, in the heating mode the temperature at which hot water is driven is significantly lower than the temperature that can be reached in a boiler. If the drive temperature in a gas boiler is of about 70-75°C, the common drive temperature in a heat pump is 40-45°C. This implies the need to replace radiators with fan coils or to install underfloor heating, given that the necessary heat emission power is not achieved with this temperature. There are special heat pumps to raise this drive temperature, but their performance is significantly inferior, and furthermore, in this case, they are not capable of working in the cooling mode. On the other hand, conventional radiators are only intended for the diffusion of heat, not cold.

[0031] The proposed thermal retrofitting system overcomes these problems. The present invention allows changing a boiler for a heat pump by reusing the hydraulic ring of pre-existing radiators in the room or dwelling, for the diffusion of both heat and cold. The invention replaces the operation of a gas boiler for heating by distributing heat through a water circuit and emitting the same heat through radiators.

[0032] Additionally, if the temperature is regulated to sufficiently lower it, water condensation may even occur such that the room is dehumidified.

[0033] In the field of the present invention, it shall be understood that the mentioned thermoelectric devices are based on Seebeck effect. This invention proposes an additional heat pumping between the surface of the radiator and the frame, as a result of the thermoelectric devices, which maintain a temperature difference between their faces approximately proportional to a supply voltage applied thereto, as a result of Seebeck effect. In this way, the surface of the thermoelectric device in contact with the radiator will be colder than the surface of the radiator, absorbing heat, while the surface of the thermoelectric device in contact with the frame will be hotter than said frame, dissipating heat. The temperature of the frame will increase in those conditions with respect to the environment, increasing its heat diffusion capacity (with the help of fans, when they are present in certain embodiments of the invention, which will reduce the coefficient of convection).

[0034] In another preferred embodiment, the heat transfer fluid flow control module of the thermal retrofitting system is configured to provide values of the flow rate of the heat transfer fluid entering the radiator of between 300 and 1000 l / hour.

[0035] In this embodiment, the maximum flow rate (1000 l / hour) occurs when the thermovalve is completely open.

[0036] The invention comprises one or more thermovalves (also referred to as thermostatic valves), which can regulate the flow rate of water going through the radiator. Advantageously, this thermovalve can be closed, hindering the flow of water when there is no need for heating / cooling (for example, when an area is not occupied or it has been determined that temperature control is not necessary), while it can be gradually opened according to temperature control needs. The definitive value of the flow rate of heat transfer fluid depends on the total head loss of the hydraulic circuit and of the specific drive pump that has been installed.

[0037] Advantageously, certain embodiments of the invention allows the possibility of regulating three elements (thermoelectric devices, fans, and thermovalve) in a coordinated manner to control the temperature of the room (heating, cooling, and dehumidifying) precisely and in accordance with the needs of the space (which can be different from the spaces the temperatures of which are controlled by the rest of the radiators within the same water distribution loop).

[0038] Thermovalves are devices which regulate the opening of the valve for the entry of fluid to the radiator, and therefore regulate the flow rate of heat transfer fluid between a cold and / or heat emission source (a reversible heat pump) and the radiator. The flow rate will depend on the water circuit installation existing in the building where the thermal retrofitting system of the invention is installed.

[0039] Advantageously, the invention is coupled in existing radiators, which allows increasing the heat provided by each of the radiators individually (as a result of the control of thermovalve and the thermoelectric devices based on the actual need of the room), as well as adding to said radiators a second use as a cooling unit (as a result of the installation of fans and thermoelectricity) and a dehumidifier (with condensation collection), adapting to the use and comfort circumstances required.

[0040] In preferred embodiments, the thermal retrofitting system further comprises: a control module for the fans configured to operate the fans and to establish the range of revolutions of said fans; wherein the processing and regulating unit is configured to communicate with the control module for the fans and to activate said control module when the room temperature of the room is lower than a setpoint temperature if at least one preestablished heating ramp is not reached after a first predetermined time from the activation of the heat pump in the heating mode and the opening of the thermovalve has elapsed.

[0041] In preferred embodiments, the control module for the fans is further configured to increase the range of revolutions of said fans every first predetermined time if the heating ramp is not reached.

[0042] Advantageously, this embodiment allows gradually increasing the speed of the fans based on whether or not the heating ramp has been reached, at least until the setpoint temperature is reached.

[0043] In preferred embodiments, the thermal retrofitting system comprises one or more fans. The number of fans will depend on the width of the radiator in which the thermal retrofitting system will be installed, as well as on the heat emission required in the room. Preferably, the number of fans in the radiator is comprised in the range of 2-8. In even more preferred embodiments, said fans are located inside the frame.

[0044] In preferred embodiments, the fans can be regulated in a range of speed of between 400 and 1500 rpm. In preferred embodiments, the fans are substantially rectangular and have a surface measuring 12 x 12 cm 2< . In preferred embodiments, the fans are continuously powered at voltages of 12 V. In certain embodiments, the fans do not exceed 1000 rpm, so that they work silently.

[0045] In preferred embodiments, the fans are regulated by means of a pulse width modulation signal (PWM signal).

[0046] In preferred embodiments, the thermal retrofitting system is characterized in that: the control module for the fans is configured to establish the range of revolutions of between 400 and 1500 rpm; the preestablished heating ramp is 0.5°C / h; the first predetermined time is 0.25 h; and / or the increase in the range of revolutions of the fans every first predetermined time is at least 450 rpm.

[0047] In some of these embodiments, a gradual increase of the revolutions of the fans is applied.

[0048] In a preferred embodiment, the thermal retrofitting system further comprises: a power supply module for the thermoelectric devices configured to provide the supply voltage of the thermoelectric devices and to regulate the supply voltage of the thermoelectric devices as long as the setpoint temperature is not reached; wherein the processing and regulating unit is configured to activate the power supply module for the thermoelectric devices when the room temperature of the room is lower than a setpoint temperature if at least the preestablished heating ramp is not reached after the first predetermined time from the activation of the reversible heat pump in the heating mode and the opening of the thermovalve has elapsed at least twice.

[0049] Advantageously, this embodiment allows adjusting the different mechanisms of the thermal retrofitting system based on the speed with which the room is being heated to reach the setpoint temperature: first, operation is performed exclusively on the flow rate of heat transfer fluid of the radiators; if the above is not sufficient, the fans are also activated, increasing their range of revolutions gradually; and finally, if the two preceding points are not enough, the thermoelectric devices are additionally activated in an auxiliary manner to achieve the desired heating.

[0050] In a preferred embodiment, the processing and regulating unit is configured to regulate the flow rate of heat transfer fluid based on the temperature of the room where the radiator is located and on the setpoint temperature to be reached in said room.

[0051] In an embodiment of the thermal retrofitting system: the processing and regulating unit is configured to activate the reversible heat pump in a cooling mode when the room temperature of the room is higher than the setpoint temperature to be reached, such that the processing and regulating unit is configured to activate the heat transfer fluid flow control module, to completely open the thermovalve, and to set the maximum flow rate of water available in the radiator as long as the setpoint temperature is not reached; and the control module for the fans is configured to operate at the maximum range of revolutions of said fans as long as the setpoint temperature is not reached.

[0052] Advantageously, this embodiment also utilizes the cooling mode of the reversible heat pump. In this case, given that the temperature of the room is to be reduced, the fans are actuated at maximum from the start in order to reach the setpoint temperature as soon as possible.

[0053] In the cooling mode the radiator will receive cold water from the circulation pump through the water circuit. The radiator is not designed for cooling, so it is not capable of cooling the air of the spaces effectively. However, with the installation of the thermoelectric devices, the temperature of the face in contact with the metal plate can be lowered, increasing its cooling capacity. The cold water, like the hot water, goes through the radiator. In this case, it absorbs part of the heat and heats up. The heat which it is capable of absorbing (and therefore, cooling the room) also depends on the rise in temperature between the mean temperature of the radiator and the room, except that, in the case of cooling, this rise in temperature is barely 10-15°C. This system increases the cooling capacity, firstly as a result of the fans which, by increasing the coefficient of convection, increase the heat that is exchanged, and secondly, as a result of the thermoelectric devices which lower the temperature of the outer metal plate, and therefore increase the cooling capacity. Therefore, the combined action of the fans and the thermoelectric devices of the invention increase cooling capacity.

[0054] Advantageously, the thermal retrofitting system of the present invention comprises a smart frame which, coupled on the existing radiators, allows giving this equipment a second life, pumping heat between the radiator and the casing with thermoelectric technology, improving their heat diffusion capacity and adding cold diffusion capacity.

[0055] In a preferred embodiment of the thermal retrofitting system: the processing and regulating unit is configured to activate the power supply module for the thermoelectric devices when the room temperature of the room is higher than a setpoint temperature if a preestablished cooling ramp is not reached after a second predetermined time from the activation of the reversible heat pump in the cooling mode and the opening of the thermovalve has elapsed.

[0056] Advantageously, this embodiment includes the activation of the thermoelectric devices to achieve an additional cooling of the room if the activation of the heat pump in the cooling mode and the activation of the fans at maximum speed are not sufficient for cooling the room at a suitable speed.

[0057] In a preferred embodiment of the thermal retrofitting system: the preestablished cooling ramp is -0.5°C / h; and / or the second predetermined time is 0.25 h.

[0058] In this way, if the temperature of the room is not reduced at a suitable speed (in this embodiment, promoting at least a decrease of 0.5°C / h), then the thermoelectric devices are activated in an auxiliary manner.

[0059] In some embodiments, the first and second predetermined times coincide with one another. In other embodiments, the values of these parameters differ from one another.

[0060] In a preferred embodiment, the frame further comprises a condensate collection tray adapted to be arranged in the lower portion of the radiator.

[0061] In this preferred embodiment, when the invention works in the cooling mode, the outer metal plate of the radiator can cause water condensation. To that end, the condensate tray is arranged in the lower portion of the radiator to collect said water. In that sense, the thermal retrofitting system also add capacity for dehumidifying the room where the radiator is installed.

[0062] The capacity to lower air temperature depends on the humidity in the room where the invention is deployed. If the air is very humid (as is generally the case in coastal towns), when the temperature of the outer metal plate is below the dew temperature, condensation occurs. The thermoelectric devices allow regulation of the temperature of the outer metal plate, which facilitates dehumidification, if this is sought.

[0063] In preferred embodiments, the condensates collected in the condensate tray are lead to a drainage of the thermal retrofitting system. In alternative embodiments, the condensates are absorbed by means of a water retention system which is part of said embodiments of the invention. In these last embodiments, the water retention system comprises: a container made of sodium and / or potassium acrylate (materials capable of absorbing 250-500 times their weight in water); and / or one or more capillaries configured to discharge said condensates out of the thermal retrofitting system.

[0064] In preferred embodiments, the thermal retrofitting system further comprises: the reversible heat pump and / or the one or more radiators.

[0065] With respect to the control and regulating unit, it is configured to operate the following system control parameters in a coordinated manner: the flow rate of water of the radiator, the power of the thermoelectric devices (for example, regulating the supply voltage of said devices), the range of revolutions of one or more of the fans, etc. Advantageously, this allows adapting the radiator with the thermal retrofitting system according to the thermal needs of the space where it is installed.

[0066] In some embodiments of the invention, the temperature of the room will be regulated by modifying the supply voltage of the thermoelectric devices. The greater the difference between the temperature of the room and the setpoint temperature (or preestablished temperature for the room), the higher the supply voltage is. With a smaller difference, the supply voltage of the thermoelectric devices is reduced. In other words, the supply voltage of the thermoelectric devices is proportional to the temperature difference between the room (room temperature) and the preestablished temperature to be reached.

[0067] For example, a controller which acts on said supply voltage of proportional to the temperature difference between the setpoint temperature and the temperature of the room, or a PID controller, can be used for regulating the supply voltage of the thermoelectric devices.

[0068] In the embodiments in which a PID controller is used for regulating the power supply of the thermoelectric devices, said controller monitors three components: Proportional component: this will be the main term that applies a voltage based on the difference between the temperature of the room and the temperature set on the thermostat. Integral component: this term assesses the inertia of the system, increasing the voltage if the difference between the temperature of the room and the thermostat is constant over time. Derivative component: this term reduces the possible oscillation of the control, correcting the voltage in the case where the evolution of the temperature varies significantly at any given time.

[0069] In the embodiments with a PID controller, although the three components can be taken into account, the main component is the proportional component. In preferred embodiments of the invention, these three components are weighted, although the proportional component has a relative weight of between 0.8 and 0.9 (by 1) with respect to the total regulation applied. Advantageously, the use of the PID controller allows attenuating the regulation signal, although the use thereof is not essential for the operation of the invention.

[0070] In an example of the invention, the proportional component is about 3V / °C. In another embodiment, the integral component exhibits an integration time of 15 min and a derivative component very low (close to 0). However, in any case, these parameters must be configured based on temperature control needs.

[0071] Likewise, when the temperature of the room drops with respect to the setpoint temperature (which can be fixed, for example, by means of a thermostat, also included in preferred embodiments of the invention), the fans in those embodiments of the invention having said fans can also be activated. The installation of the fans in the frame favors the dissipation of heat (or cold), reducing thermal resistance, and therefore increasing heating (or cooling) capacity of the radiator. The rotational speed of the fans will be proportional to the temperature difference between the setpoint temperature and the room temperature in the room the temperature of which is to be controlled. Therefore, the power dissipated by the assembly of the radiator and the thermal retrofitting system is greater the higher the supply voltage applied on the thermoelectric devices is and the higher the rotational speed of the fans is.

[0072] In the invention, the number of thermoelectric devices depends on the heat emission required of the improved radiator with the thermal retrofitting system, as well as on the width of the frame.

[0073] In preferred embodiments, the thermoelectric devices are powered with voltages between 0 and 12 V and the heat emission is virtually proportional to the supply voltage.

[0074] In a more preferred embodiment, the processing and regulating unit of the thermal retrofitting system comprises a controller configured to regulate the flow rate of heat transfer fluid, the supply voltage of the thermoelectric devices, and / or the range of revolutions of the fans function in a manner proportional to the temperature difference between the radiator and the environment of the room.

[0075] In one embodiment, the thermal retrofitting system comprises a PID controller configured to regulate the control parameters in a manner proportional to the temperature difference between the radiator and the environment of the room. In these embodiments, the supply voltage applied will be regulated by means of a PID controller where the proportional term prevails, such that the voltage applied will depend on the difference between the temperature of the room and the preestablished setpoint temperature.

[0076] In preferred embodiments, the thermal retrofitting system comprises: one or more presence sensors installed in the room where the radiator is located and communicated with the processing and regulating unit, configured to detect the presence of people inside the room; a thermostat configured to establish a setpoint temperature to be reached in the room, said thermostat being communicated with the processing and regulating unit.

[0077] In preferred embodiments, the thermal retrofitting system comprises: one or more temperature sensors installed in one or more of the following locations: in the room, on at least one of the faces of the one or more thermoelectric devices, in the frame, in the heat transfer fluid inlet of the radiator, said temperature sensors being communicated with the processing and regulating unit.

[0078] In these embodiments with temperature sensors, the control and regulating unit is configured to continuously monitor the temperature of the room through the one or more temperature sensors (or probes) and to use the temperature measurements in the regulation of the thermal retrofitting system.

[0079] In preferred embodiments, the thermal retrofitting system comprises one or more of the following sensors: Temperature sensor for detecting the ambient temperature in the room. Temperature sensor for detecting the ambient temperature outside the room Temperature sensor for the heat transfer fluid. Temperature sensor for the outer face of the frame (in the outer casing).

[0080] In other embodiments, the thermal retrofitting system comprises one or more of the following sensors: Temperature sensor for the inner face of the thermoelectric device (i.e., the face of the thermoelectric device proximal to the radiator). Temperature sensor for the outer face of the thermoelectric device (i.e., the face of the thermoelectric device distal to the radiator; in other words, proximal to the frame). Temperature sensor for the inner face of the frame.

[0081] In these embodiments with sensors, the measurements obtained by the sensors can be taken into account in the regulation of the thermoelectric devices, the fans, and / or the thermovalve.

[0082] If the temperature of the room drops with respect to the setpoint temperature and the power dissipated by the radiator is insufficient (either because the capacity of the heat pump is insufficient or because the external temperature is too low), the thermoelectric devices will be activated with a voltage sufficient to increase the heat provided to the room. Moreover, the dissipation capacity of the radiator (with the casing) increases because the surface temperature of the outer casing increase. Moreover, the temperature of the water leaving the radiator is reduced. The lower the return temperature to the water circuit in the heat pump is, the better its performance will be.

[0083] In preferred embodiments, the processing and regulating unit is configured to activate the heat transfer fluid flow control module, the control module for the fans, and / or the power supply module for the thermoelectric devices based on the temperature of a heat transfer fluid entering the radiator through the fluid inlet.

[0084] In preferred embodiments, the thermal retrofitting system comprises: one or more environmental humidity sensors installed in the room where the radiator is located, configured to measure the relative humidity in said room.

[0085] In these embodiments, the control and regulating unit is configured to continuously monitor the relative humidity of the room through said one or more environmental humidity sensors. The humidity and temperature of air define its enthalpy. Using the humidity and temperature measurements of the air in preferred embodiments of the invention allows knowing the dew temperature, and therefore determining the temperature at which condensation occurs. This is important in the cooling mode of the invention given that the higher the humidity, the higher the dew temperature, and therefore the temperature of the outer metal plate (cooled by the thermoelectric devices) can be adapted based on the cooling and / or dehumidifying needs. One skilled in the art know how to determine the dew temperature in this context.

[0086] In preferred embodiments of the thermal retrofitting system comprising both the one or more ambient humidity sensors and the condensate tray, the processing and regulating unit is configured to activate the power supply module for the thermoelectric devices based on the relative humidity in the room and the amount of condensates in the condensate tray.

[0087] Advantageously, the claimed system can regulate condensation such that the relative humidity of the room, measured with the humidity sensors, is set at a predetermined value. In this way, dehumidification can be regulated. Likewise, the condensate tray can work as a humidifier in winter.

[0088] For example, in this embodiment: If the room is below the predetermined desired humidity value, the temperature of the thermoelectric devices is increased to favor the evaporation of the contents of the condensate tray. If the room is above the predetermined desired humidity value, the temperature of said thermoelectric devices will be lowered.

[0089] In preferred embodiments, the thermal retrofitting system comprises mechanical fastening means adapted to attach the frame to one of the thermoelectric devices and to the radiator, wherein said fastening means in turn comprise: a radiator anchoring and a frame anchoring surrounding the thermoelectric device; wherein the radiator anchoring is arranged on a first face of the thermoelectric device and the frame anchoring is arranged on a second face of the thermoelectric device opposite the first face; a screw going through the frame, the radiator anchoring, the frame anchoring, and at least one of the thermoelectric devices, one or more washers arranged at the ends of the screw.

[0090] In preferred embodiments, the radiator anchoring and / or the frame anchoring are metallic parts.

[0091] In more preferred embodiments, the washers are made of nylon.

[0092] In preferred embodiments, the fastening means further comprise a layer of thermal paste applied at the interface between each of the faces of the thermoelectric device and each of the parts.

[0093] In alternative embodiments not comprising mechanical fastening means, the thermal retrofitting system further comprises magnetic fastening means adapted to fix each of the thermoelectric devices between the frame and the radiator.

[0094] In preferred embodiments, the magnetic fastening means comprise two neodymium magnets arranged on the frame and the radiator, respectively, surrounding each of the thermoelectric devices.

[0095] In preferred embodiments of the invention, the frame is manufactured from a metallic material, preferably aluminum and / or galvanized metal plate.

[0096] In this way, the invention relates to a thermal retrofitting system comprising a casing suitable for installation thereof in a radiator. Said system, by means of a series of thermoelectric devices, pumps heat between the surface metal plate of the radiator and the environment, boosting the heating capacity of the radiator and / or providing it with cooling capacity.

[0097] The heating mode acts when the temperature of the water circulating through the radiator is not high enough for the temperature of a room where the radiator is installed to reach a preestablished temperature value. In this case, the thermoelectric devices installed between the surface metal plate of the radiator and the frame are activated. This increases the temperature of the frame, and therefore heats up the environment more at the expense of cooling the water in the radiator. This effect makes the water circuit, which supplies heat transfer fluid to the radiators, work at a lower temperature. Therefore, said water circuit can be heated using a thermal generator at a lower temperature, such as the case of a heat pump (an aerothermal system). In this way, it can replace the boilers which require a higher driving or operating temperature.

[0098] The lower the drive temperature of the heat pump is, the greater the performance thereof is generally. Moreover, the lower the temperature outside a building is, the lower the heating capacity of an aerothermal system is (therefore the lower the drive temperature is) such that the thermal retrofitting system of the invention acts as a back-up to complement the heating capacity of the aerothermal system in these cold conditions outside. In other words, the thermal retrofitting system acts as an additional heat generator to complement a reversible heat pump which provides the hot water that enters the radiator.

[0099] In preferred embodiments of the thermal retrofitting system of the invention, the heating mode operates as follows: The thermovalves limit the passage of the heat transfer fluid (water) when an area in the room where the radiator is located is not occupied or when it has been determined that said area will not be heated. The valves are configured to allow the passage of a flow rate of water ranging from at least about 300 l / h to at most 1000 l / h. When the temperature of the room is below a preestablished temperature to be reached (setpoint temperature), the heat pump turns on and water flows through the hydraulic circuit. In those rooms determined as being in use (either by detection or by scheduling), the thermovalves will open to allow the passage of the maximum flow rate (the thermovalve opening completely, as explained in the preceding point). If the heating ramp (i.e., the speed at which the temperature drops) of the room does not exceed a given threshold (for example, 0.5°C / h) then the fans are put into operation, going from a lower speed (for example, 400 revolutions per minute, rpm) to a higher speed (for example, 1500 rpm) with a PWM regulation system configured to increase their rotational speed by 450 rpm every 15 min if the heating ramp requirement of at least the preestablished threshold (for example, 0.5°C / h) is not met. In other words, if the room is not heated quickly enough with the operation of the thermovalves, then the fans are actuated in an auxiliary manner. If the heating ramp is insufficient even with the activation of the fans, then the thermoelectric devices turn on, regulating their supply voltage by means of a PID controller configured to reach the setpoint temperature of the room.

[0100] Moreover, the preferred embodiments of the thermal retrofitting system of the invention have a cooling mode. This way of cooling is activated when the temperature of the room in which the radiator is installed is higher than a preestablished temperature to be reached. In this case, cold water is circulated through the radiator, with the ability to boost the effect thereof by pumping heat between the casing and the surface metal plate of the radiator (in reverse compared to operation in the heating mode). In this case, the temperature of the frame of the invention is lowered at the expense of heating the water in the radiator. The water then circulates through the circuit of preexisting radiators in the room and returns to the generation unit, in this case, the heat pump. In this way, the radiator (which is originally use as a heater) is converted into a cold diffuser.

[0101] In more preferred embodiments, the cooling mode operates as follows: When cooling of a room is needed, a reversible heat pump is capable of cooling water, driving the fluid at a temperature lower than the temperature of the room (for example, 7°C) generally, and returning at a temperature higher than the previous temperature (for example, 12°C). The radiators themselves are not capable of suitably dissipating this cold (i.e., capturing heat from the environment). However, like in the heating mode, the thermostatic valves of the invention are configured to open the passage of water in those radiators located in the area where cooling is required. In the cooling mode, the fans are put into operation from the start and at the maximum range of revolutions (for example, 1500 rpm). If the device is not capable of absorbing the load for cooling the room (i.e., if the temperature does not go down despite the fans being activated), the thermoelectric devices are activated in a regulated manner by means of a PID controller.

[0102] In preferred embodiments, the thermal retrofitting system comprises a heat pump regulating module. In this way, the thermal retrofitting system can estimate the overall performance of the temperature control installation and, by knowing the number of rooms to be heated and the power required, the optimum water drive temperature (the lowest possible in principle) can be calculated, deciding to activate the frame only in the rooms where heating is required.

[0103] In a second inventive aspect, the invention provides a method for updating a radiator by means of using the thermal retrofitting system according to any of the embodiments of the first inventive aspect, wherein said method comprises performing the following steps: providing a radiator having a fluid inlet and a fluid outlet, said radiator being connected to a reversible heat pump; and fixing, using the fastening means, the thermal retrofitting system to the radiator; such that the radiator and the thermoelectric devices are in thermal contact; and configuring said thermovalve to provide values of the flow rate of the heat transfer fluid entering the radiator of between 300 and 1000 l / hour.

[0104] In preferred embodiments, the method further comprises: configuring the control module for the fans configured to establish an range of revolutions of said fans of between 400 and 1500 rpm.

[0105] In preferred embodiments, the method further comprises: configuring the power supply module for the thermoelectric devices configured to provide a supply voltage of the thermoelectric devices of between 0 and 12 V.

[0106] As a result of the control module for the fans, temperature can be regulated through the indirect regulation of the coefficient of convection. The natural coefficient of convection is in a range of 2-20 W / m 2< K. This coefficient is raised to 25-300 W / m 2< K using forced convection by means of the control module for the fans, based on the speed of the fans.

[0107] To summarize the invention: The invention uses the thermoelectric devices both for heating and for cooling and / or dehumidifying interior spaces. The invention is designed to be integrated with an existing radiator. The invention allows providing greater functionality to a conventional radiator, going from being a mere heat dissipator with power given by the temperature of the water reaching it through the pipes of the building where it is installed to being an element with a certain degree of autonomy, which allows heating, cooling (which is not possible with a conventional radiator), and even dehumidification. The invention allows the receiving radiators to work with a high heat emission when combined with a heat pump, such that said heat pump provides hot water to the radiator, entering the radiator through the water circuit. The heat pump operates with a driving temperature (40-45°C) that is lower than the boiler (about 70-75°C).

[0108] The solution proposed in the present invention presents several benefits: Reduction of environmental impact derived from the reduction of scraps (about 80 kg of aluminum per dwelling, equivalent to 1.2 tons of CO 2 ) and debris from the corresponding work. Expansion of the common heating functionality of the radiator to provide temperature control, i.e., making it possible to furthermore cool and dehumidify the retrofitted spaces, a key aspect in the future. Improvement in thermal comfort and possibility of regulating the new temperature control system. The heat pumping capacity at the radiator level allows a distributed temperature control, while at the same time optimizing the overall efficiency of the temperature control installation in the building. Compensation for temperature control limitations in an aerothermal system by increasing heating power by 20% when the external temperature drops significantly. Reduction of installation times with respect to other temperature control alternatives (75% savings in installation time with respect to the installation of fan coils and 93% with respect to underfloor heating). Reduction of economic costs, with an estimated savings of about 50% with respect to the installation of new fan coils and 66% with respect to underfloor heating.

[0109] All the features of the system and / or the steps of the methods described in this specification (including the claims, description, and drawings) can be combined in any combination, with the exception of the combinations of such mutually exclusive features.DESCRIPTION OF THE DRAWINGS

[0110] These and other features and advantages of the invention will be more apparent based on the following detailed description of a preferred embodiment given only by way of illustrative and non-limiting example in reference to the attached figures. Figure 1 shows an exploded view of a conventional radiator to which an embodiment of the thermal retrofitting system of the invention has been incorporated. Figure 2 corresponds to a top view of the frame of an embodiment of the thermal retrofitting system of the invention, once installed on the radiator. Figure 3a) shows a side view of an embodiment of the thermal retrofitting system of the invention, once installed on the radiator. Figure 3b) illustrates an enlarged view of the mechanical fastening system used in this embodiment of Figure 3a). Figure 4 depicts a preferred embodiment of the thermal retrofitting system of the invention, which is connected to several additional control modules to regulate the water flow entering and exiting the radiator, as well as to control the operation of the fans (thereby regulating the coefficient of convection) and to supply power to the thermoelectric devices. Figures 5-8 depict the different steps of an embodiment of the method for updating a radiator according to the present invention, which comprises the use of the retrofitting system to expand the functionality of the radiator. In particular: Figure 5 depicts the first step of the method, where the step starts from a pre-existing radiator. Figure 6 illustrates how thermoelectric devices are incorporated in the radiator. Figure 7 shows how the frame is fixed on the radiator. Figure 8 corresponds with the installation of the thermovalve in the fluid inlet of the radiator.

[0111] The table below lists all the reference numbers that appear in the preceding figures: ReferenceElement1Radiator1.1Metal plate of the radiator2Fans3Thermovalve or thermostatic valve4Frame or casing4.1Slots in the front portion of the frame4.2Holes in the upper portion of the frame5Thermoelectric device6Fastening means6.1First part or radiator anchoring6.2Second part or frame anchoring / casing6.3Screws6.4Insulating thermal paste6.3.1, 6.3.2Washers7Condensate collection tray8Heat transfer fluid (e.g., water) flow control module8.1Fluid inlet in the radiator8.2Fluid outlet of the radiator9Control module for the fans (to control the coefficient of convection)10Power supply module for the thermoelectric devices11Processing and regulating unit DETAILED DESCRIPTION OF THE INVENTION Embodiments of the thermal retrofitting system

[0112] Some embodiments of the invention illustrated in Figures 1 to 8 will be explained in greater detail in this section. Furthermore, it shall be assumed that the thermal retrofitting system (100) of the invention is installed in a conventional radiator (1) arranged in a room of a building, which has a water circuit providing a fluid that enters the radiator (1).

[0113] As shown in Figure 1, the thermal retrofitting system (100) of the invention is adapted for installation in a radiator (1), such that it expands the functionality of said radiator. The radiator (1) comprises a metal plate (1.1), a fluid inlet (8.1), and a fluid outlet (8.2). The radiator (1) receives water from the water circuit of the building through the fluid inlet (8.1), while the fluid is returned to the water circuit through the fluid outlet (8.2).

[0114] The thermal retrofitting system (100) comprises a frame (4) and one or more thermoelectric devices (5) that are powered with a specific voltage and can work in two different modes: heating mode (in which heat is pumped between the radiator (1) and the frame (4) of the invention) and cooling mode. In the heating mode, the temperature of a front casing (4.1) of the frame (4) is raised and the water in the radiator (1) is cooled. The opposite happens in the cooling mode.

[0115] As can be seen, the frame (4) comprises a plurality of slots (4.1) in the front portion, as well as a plurality of holes (4.2) in the upper portion thereof. These holes (4.2) are illustrated in greater detail in the top view of the frame (4) of Figure 2. Furthermore, the embodiment of the thermal retrofitting system (1) of Figure 1 comprises: fans (2) arranged in the frame (4) and configured to increase the coefficient of convection, favoring heat exchange between a casing (4.1) of the frame (4) and the environment; and a thermovalve (3) arranged in the fluid inlet (8.1) of the radiator configured to regulate the flow rate of the water passing through the radiator.

[0116] In Figure 3a), the fans (2) are arranged in the upper portion of the frame (4), although this location is not essential. In other embodiments of the thermal retrofitting system (100), the fans (2) are arranged in the casing (4.1) of the frame (4), as illustrated in the embodiment of Figure 4.

[0117] Moreover, the thermal retrofitting system (100) comprises fastening means (6) configured to provide a good thermal contact between the radiator (1) and the thermoelectric devices (5). Likewise, the fastening means (6) are adapted to allow the diffusion of heat, for example, being manufactured with a thermal conductive material (for example, galvanized metal plate, aluminum, or another metal).

[0118] In the field of the present invention, a good thermal contact shall be understood to mean contact which preferably has a thermal resistance less than or equal to 4 × 10 − 4 m 2 K W , which is equivalent to 1 mm of thermal paste and 2 cm of steel. In general, a layer of thermal paste that is as thin as possible, preferably with a thickness not exceeding 1 mm, is suitably used in the invention. In this way, the thermal conductivity of the paste material is not as critical as a homogenous distribution of the paste between the surfaces to be thermally coupled of the invention.

[0119] An example of these fastening means (6) is illustrated in Figure 3a) in which two mechanical fastening means (6) can be seen. Each of these fastening means (6) comprises a first part or radiator anchoring (6.1) and a second part or frame anchoring (6.2) which are coupled to the frame (4) and surround the thermoelectric devices (5) like a sandwich. The parts (6.1, 6.2) are fastened to the thermoelectric devices (5) by mechanical fastening means, particularly screws (6.3) and washers (6.3.1, 6.3.2), as can be seen in the enlarged view of Figure 3b). In this example, first washers (6.3.1) can be found in the interface between the metal plate (1.1) of the radiator (1) and the first part or frame anchoring (6.1), while second washers (6.3.2) can be found in the interface between the second part or frame anchoring (6.2) and the frame (4). In other words, the thermoelectric devices (5) are fixed between the first part or radiator anchoring (6.1) and the second part or frame anchoring (6.2) on the inside of the frame (4). The first washers (6.3.1) are proximal with respect to the radiator (1), while the second washers (6.3.2) are proximal with respect to the frame (4) (i.e., distal with respect to the radiator (1)).

[0120] In preferred embodiments, the washers (6.3.1, 6.3.2) attaching the radiator anchoring (6.1) and the frame anchoring (6.2) are made of nylon to facilitate thermal bridge breakage.

[0121] In the embodiment of Figure 3b), it can be seen how the radiator anchoring (6.1) is arranged between the metal plate (1.1) of the radiator (1) and the thermoelectric device (5). In this way, the fastening means (6) are adapted to allow thermal contact between the radiator (1) and the thermoelectric devices (5).

[0122] In preferred embodiments, a thermal paste (6.4) is used to improve the thermal coupling between the radiator (1) and the thermoelectric devices (5). More preferably, the thermal paste (6.4) has a silicone-, ceramic-, or metal-based composition. In certain embodiments, the thermal paste (6.4) is filled with high thermal-conductivity metals (for example, silver, aluminum, gold, or alloys thereof), metal oxides (of zinc or aluminum), or boron nitrite.

[0123] In preferred embodiments, a layer of thermal paste (6.4) with a thickness less than or equal to 1 mm is used. In even more preferred embodiments, the layer of thermal paste (6.4) has a substantially uniform thickness and is homogenous (i.e., preventing air bubbles from being trapped therein). Advantageously, thermal coupling is superior when the thermal paste is homogenously distributed. To that end, tightening of the elements of the invention that are thermally coupled through the thermal paste must be uniform and sufficient to ensure that the layer of thermal paste is as thin and as uniform as possible.

[0124] The frame (4) is adapted to dissipate heat to the environment in the heating mode, while it is adapted to cool the environment in the cooling mode. To that end, the power supply received by the thermoelectric devices (5) is adapted, as will be explained below.

[0125] As can be seen in the embodiment of Figure 3a), there is arranged at the bottom of the frame (4) a condensate collection tray (7) which is useful when working in the cooling mode. In the case of working in the cold mode, the casing or frame (4) may cause condensation of water that would be collected in the lower portion of the radiator (1).

[0126] The final performance of the invention greatly depends on achieving a good thermal contact between the thermoelectric devices (5) and the radiator (1), as well as between the thermoelectric devices (5) and the frame (4). If the parts (6.1, 6.2) that put the thermoelectric devices (5) in contact with the frame (4) or the radiator (1) are poorly machined, or if thermal paste (6.4) is absent, elevated thermal resistances may be produced, which can cause a 10% drop in overall system performance (i.e., heat emission capacity). To prevent same, preferred embodiments of the invention (such as that illustrated in Figure 3) proposes the following: Fastening the thermoelectric device (5) to the radiator (1) by means of a radiator anchoring (6.1) manufactured from a metallic material, wherein said radiator anchoring (6.1) is located behind the visible outer metal plate (1.1) of the radiator (1). Then, a metallic frame anchoring (6.2) is placed which, together with the radiator anchoring (6.1), surround the thermoelectric device (5) like a sandwich. The two metallic parts are separated by an insulating material. A conductive thermal paste (6.4) is applied between the metallic anchorings (6.1, 6.2) and the thermoelectric device (5) to ensure a good thermal contact. Finally, two screws (6.3) or bolts go through the two parts (6.1, 6.2), with the outer metal plate (1.1) of the radiator (1) being arranged between them. The screws (6.3) are supported on the radiator anchoring (6.1) and on the frame anchoring (6.2) with nylon washers to reduce the thermal bridge between said anchorings (6.1, 6.2). Preferably, tightening applied by means of screws (6.3) and washers (6.3.1) for the attachment of the radiator anchoring (6.1) and the metal plate (1.1) must be at least 5 Nm. Also preferably, said tightening is uniform in said attachment. The frame (4) is anchored to the frame anchoring (6.2) by means of screws (6.3) and washers (6.3.2) directly (given that, in this case, thermal bridge breakage is not necessary) with tightening of at least 4 Nm.

[0127] In preferred embodiments, the frame (4) is made of a metallic material, preferably aluminum and / or galvanized metal plate. Advantageously, this favors the dissipation of heat from one of the outer faces of the thermoelectric devices (5) to the room environment. This heat dissipation effect can be reinforced as a result of the fans (2) in those embodiments of the invention comprising same.

[0128] It should be highlighted that although the fastening means (6) of Figure 3 are of mechanical origin, in other embodiments of the thermal retrofitting system (100), the fastening means can be magnetic means.

[0129] Figure 4 shows another embodiment of the thermal retrofitting system (100) of the invention, showing the details of the control modules involved in the system. In particular, the thermal retrofitting system (100) comprises: a heat transfer fluid flow control module (8) which is configured to operate the thermovalve (3) and to set the flow rate of water entering the radiator (1). a control module (9) for the fans (2), which is configured to regulate the range of revolutions of said fans (2), thereby regulating the coefficient of convection of the thermal retrofitting system (100) and favoring heat exchange between the frame (4), the radiator (1), and the environment of the room. a power supply module (10) for the thermoelectric devices (5), which is configured to set the operating voltage of the thermoelectric devices (5) based on room temperature of the room where the thermal retrofitting system (100) and the radiator (1) are located, as well as on the target temperature. For example, the power supply module (10) comprises a battery providing direct current. In a preferred embodiment, the power supply module (10) is regulated with a PID controller with settings that can be regulated for the proportional, integral, and derivative components.

[0130] In this preferred embodiment, the modules (8, 9, 10) are connected to and regulated in a centralized manner by a processing and regulating unit (11) which acts as a control unit that automatically establishes the values of the control parameters that said modules (8, 9, 10) subsequently apply on the fans (2), the thermovalve (3), and the thermoelectric devices (5). In other words, the processing and regulating unit (11) supplies electric power to the thermoelectric devices (5), the fans (2), and / or the thermovalve (3); and based on temperature control needs of the room and on the temperature of the water entering the radiator (1), said processing and regulating unit (11) is configured to establish the supply voltage of the thermoelectric devices (5), the supply voltage of the fans (2), and the passage flow rate of the thermostatic valve (3).

[0131] Likewise, the processing and regulating unit (11) is communicated with a reversible heat pump (not depicted in the figures). This heat pump is responsible for providing hot water to the fluid inlet (8.1) of the radiator. In even more preferred embodiments, the communication between the processing and regulating unit (11) with the heat pump is wireless.

[0132] In a preferred embodiment, the thermal retrofitting system (100) comprises presence sensors configured to automatically activate the system when they detect people in the room where the radiator (1) having said thermal retrofitting system (100) is located. Advantageously, this allows greater energy savings since the system only begins operation when the room is occupied.

[0133] In a preferred embodiment, the thermal retrofitting system (100) comprises an occupation prediction module which comprises one or more presence sensors and is connected to the processing and regulating unit (11). In this embodiment, the presence sensors are configured to collect measurements relating to presence in and occupation of the room, and then send the measurements to the processing and regulating unit (11), where said measurements are processed to estimate occupation trends.

[0134] In a preferred embodiment, the thermal retrofitting system (100) comprises temperature and / or humidity sensors configured to send temperature and / or humidity measurements of the room where the radiator (1) with said thermal retrofitting system (100) is located to the processing and regulating unit (11). Once the processing and regulating unit (11) received the parameters measured with the sensors, it sends the necessary settings to the modules (8, 9, 10).

[0135] In a preferred embodiment, the fastening means (6) are magnetic means placed directly on the radiator (1). In even more preferred embodiments, the fastening means (6) comprise neodymium magnets arranged directly on the frame (4) and adapted to exert a sufficient force to secure said frame (4) and a frame anchoring (6.2) to one another. In this embodiment, and unlike the embodiment of Figure 3, the radiator anchoring (6.1), the screws (6.3), and the washers (6.3.1, 6.3.2) are not necessary.

[0136] In another alternative embodiment, the anchoring system is a mechanical system (such as, for example, the system of Figure 3) and ensures a good thermal contact.

[0137] The fans (2) of some embodiments of the invention allow setting the coefficient of convection between the frame (4) and the air of the room. In this way, the joint regulation of the thermoelectric devices and the fans enhances the use thereof in both the heating mode and the cooling mode.

[0138] As a result of the condensate collection tray (7), the thermal retrofitting system of the invention is capable of acting as a dehumidifier with additional regulation capacity as a result of the installation of the thermoelectric devices (5).

[0139] The design of the frame (4) ensures a good heat exchange between the thermoelectric devices (5) and the environment of the room where the radiator (1) with the thermal retrofitting system (100) is installed. Advantageously, this frame (4) may have other additional uses such as being used as a drier for clothes or a heat retainer for a cup of coffee.

[0140] In preferred embodiments, the frame (4) also comprises thermoelectric devices (5). In these embodiments, the thermoelectric devices (5) are not fastened to the fastening means (6), but directly integrated in the frame (4). In this way, in these embodiments the frame (4) is an add-on which can be attached directly to the radiator (1) in a manner that can be decoupled from same.

[0141] In preferred embodiments, the thermal retrofitting system is adapted to control multiples radiators (1) installed in different rooms of the same building. In these embodiments, a single control and regulating unit (11) is configured to regulate the thermoelectric devices (5) and, where appropriate, the thermovalves (3) and the fans (2) of each of the radiators (1). Therefore, an adaptation of the temperature control of each room can be performed individually, boosting the capacity to heat and / or cool each room based on the actual needs of each of them.

[0142] In other embodiments, the thermal retrofitting system (100) can be communicated with the aerothermal heat pump or the heat generator of the building.

[0143] Throughout this description, water was considered the fluid of the radiator. However, the thermal retrofitting system of the invention works regardless of which heat transfer fluid is used.Example of the operation of an embodiment of the invention in the heating mode

[0144] The operation of an embodiment of the thermal retrofitting system (100) of the present invention, which is installed in a radiator (1), is set forth below. In turn, said radiator (1) is connected to a reversible heat pump through pre-existing installation.

[0145] For this example it shall be assumed that the room is at a first temperature (for example 15°C) and that the setpoint temperature to be reached is a second temperature, higher than the first temperature (e.g., 21°C). The setpoint temperature can be indicated, for example, through a thermostat.

[0146] Likewise, it shall be assumed that the room the temperature of which is to be controlled comprises a single radiator (1) in which the thermal retrofitting system (100) of the invention, comprising the thermovalve (3), as well as fans (2) and thermoelectric devices (5), has been installed.

[0147] In this case it shall be assumed that a presence sensor of the invention for detecting the presence of people is present, such that the occupation of the room can be detected. When it is determined that there are people in the room, the following operation of the thermal retrofitting system (100) takes place in order to heat said room and to reach the second temperature (setpoint temperature): 1) The thermovalve (3) is set to open (at least partially) the heat transfer fluid inlet (8.1) based on the difference between the temperature of the heat transfer fluid and the setpoint temperature. In some embodiments, when the temperature of the heat transfer fluid is too low (for example, at a third temperature, preferably below 40°C), then the thermovalve (3) allows all the heat transfer fluid to pass to the radiator. 2) Actuating the fans (2): If the temperature of the room does not change towards the setpoint temperature only by means of the preceding step after a first preestablished time (for example, 1-2 minutes), then the fans (2) are activated at a certain number of revolutions per minute (for example, 400 rpm), and said speed is gradually increased to a higher speed (for example, 1000 rpm). This last speed should not be the maximum speed allowed by the fan (2), so as to ensure a silent operation. 3) Actuating the thermoelectric devices (5) when the temperature of the room does not reach the setpoint temperature in a second preestablished time (for example, greater than the first preestablished time, assuming another 1-2 minutes) once the preceding steps 1 and 2 have taken place. This can occur either because the external temperature is too low, and therefore there are excessive losses in the heat pump to which the radiator is connected, or because the power of the radiator (1) is insufficient, due to a low temperature of the heat transfer fluid. In this case, the thermoelectric devices (5) must be activated by setting the supply voltage (for example, between 0 and 12 V).

[0148] In this way, the thermoelectric devices (5) heat the frame (4), raising its temperature above the temperature of the heat transfer fluid. This allows adding heat emission to the radiator (1), increasing the heat exchange efficiency of the thermal retrofitting system (100) in the room, furthermore favored by the fans (2).

[0149] The heat transfer fluid reaching the fluid inlet (8.1) of the radiator (1) at the third temperature (40°C) will experience a drop in temperature due, firstly, to the heat being given off to the environment through the surface of the radiator favored by the fans, and secondly, to the thermoelectric devices (5). The inner face of these thermoelectric devices (5), in thermal contact with the radiator (1), will cool down, which causes a reduction in the temperature of the heat transfer fluid circulating therein. The higher the voltage applied is, the greater this cooling will be.

[0150] The fluid exits the radiator (1) through a fluid outlet (8.2) colder than when it was introduced (for example, at a fourth temperature of between 35 and 39°C) and is heated again in the reversible heat pump to which the radiator (1) is connected.Example of the operation of an embodiment of the invention in the cooling mode

[0151] A different example, where the room temperature of the room is a first temperature (for example, 29°C) that is higher than a second temperature (or setpoint temperature, for example, 24°C), will be considered below. It shall also be assumed that the thermal retrofitting system (100) has a presence sensor that allows initiating regulation when it detects that the room is occupied.

[0152] Likewise, it shall be assumed that the room the temperature of which is to be controlled comprises a single radiator (1) in which the thermal retrofitting system (100) of the invention, which comprises the thermovalve (3), as well as fans (2) and thermoelectric devices (5), has been installed. Said radiator (1) will be connected to a heat pump acting in the cooling mode.

[0153] When it is determined that there are people in the room, the following operation of the thermal retrofitting system (100) takes place in order to cool said room and to reach the second temperature (setpoint temperature): 1) The thermovalve (3) is set to open (at least partially) the heat transfer fluid inlet (8.1) based on the difference between the temperature of the heat transfer fluid and the setpoint temperature. In some embodiments, when the temperature of the heat transfer fluid is relatively high (for example, at a fifth temperature, preferably above 18°C), then the thermovalve (3) allows all the heat transfer fluid to pass to the radiator (1). 2) Actuating the fans (2): If the temperature of the room does not change towards the setpoint temperature only by means of the preceding step after a first preestablished time (for example, 1-2 minutes), then the fans (2) are activated a at a certain number of revolutions per minute (for example, 400 rpm), and said speed is gradually increased to a higher speed (for example, 1000 rpm). This last speed should not be the maximum speed allowed by the fan (2), so as to ensure a silent operation. 3) Actuating the thermoelectric devices (5) when the temperature of the room does not drop to the setpoint temperature in a second preestablished time (for example, greater than the first preestablished time, assuming another 1-2 minutes) once the preceding steps 1 and 2 have taken place. This can occur either because the external temperature is too high and, therefore, there is an additional cooling need; or because the cooling capacity of the heat pump is insufficient).

[0154] In this way, the thermoelectric devices (5) cool the frame (4), lowering its temperature below the temperature of the heat transfer fluid. This allows boosting the heat exchange of the assembly of radiator (1) and thermal retrofitting system (100) in the room, favored by the fans (2). Additionally, when the surface temperature thereof is below the dew temperature of the room (for 26°C and 50% relative humidity, the dew temperature would be 14.8°C), condensation will occur in the frame (4), where it can be collected and discharged through the lower portion of the frame since a condensate collection tray (7) is installed, contributing to a reduction in the latent cooling load.

[0155] The heat transfer fluid will experience an increase in temperature due, firstly, to the absorption of heat from the environment through the surface of the radiator (1) favored by the fans (2,) and secondly, to the thermoelectric devices (5) the inner face of which, in thermal contact with the radiator (1), will heat up, which causes an increase in the temperature of the heat transfer fluid circulating therein. The higher the voltage applied is, the greater this heating will be.

[0156] Conventional cold generators (for example, air-conditioning apparatus) do not distribute their temperature control capacity through radiators (1), but rather cool the air of the room directly or using fan coils. In contrast, in the present invention the fluid exits the radiator (1) through the fluid outlet (8.2) hotter than when it was introduced and is cooled again in the heat pump to which said radiator is connected. Therefore, the thermal retrofitting system (100) is configured to add this cooling capacity to a radiator (1) by adding the effect of the fans (2) on one hand and allowing the cooling capacity by means of the thermoelectric devices (5) to be increased, reducing the temperature of the frame (4), on the other hand. In other words, the invention allows distributing the temperature control capacity of the heat pump through radiators.Embodiments of the method for the installation of the thermal retrofitting system of the invention in a pre-existing radiator

[0157] Part of the invention also relates to a method for the installation of the thermal retrofitting system (100) according to the first inventive aspect, which allows updating and expanding the functions of a pre-existing conventional radiator. This method is illustrated in Figures 5 to 8 and comprises the following steps: Step 1 (see Figure 5): Providing a radiator (1). For example, this radiator (1) can be a conventional radiator already installed in the building and usually connected to the water circuit. Step 2 (see Figure 6). Placing one or more thermoelectric devices (5) on the radiator (1) using fastening means or anchoring (6) that will be fastened to the radiator (1). For example, they can be placed on the casing (1.1) of said radiator (1), in thermal contact with same. For the sake of simplicity, the fastening means or anchoring (6) have not been depicted in Figure 6, but in this preferred embodiment said system is that of Figure 3. The fastening means (6) perform two functions: on one hand, ensuring a good thermal contact between the radiator (1) and the thermoelectric devices (5); and, on the other hand, securing the frame (4) of the thermal retrofitting system (100), which is then installed in the following step. Step 3 (see Figure 7). Installing the frame (4), which is anchored to the radiator (1) and the thermoelectric devices (5) through the fixing system or anchoring (6).

[0158] In a preferred embodiment, the method for installation optionally comprises the following step: Step 4 (see Figure 8). Installing the thermovalve or thermostatic valve (3) in the fluid inlet (8.1) in the radiator (1) next to the water stopcock at the inlet of the radiator (1). This thermovalve (3) regulates the flow rate of water entering the radiator (1) and allows setting same based on the temperature control needs of the room and the external environmental conditions.

Examples

Embodiment Construction

Embodiments of the thermal retrofitting system

[0112]Some embodiments of the invention illustrated in Figures 1 to 8 will be explained in greater detail in this section. Furthermore, it shall be assumed that the thermal retrofitting system (100) of the invention is installed in a conventional radiator (1) arranged in a room of a building, which has a water circuit providing a fluid that enters the radiator (1).

[0113]As shown in Figure 1, the thermal retrofitting system (100) of the invention is adapted for installation in a radiator (1), such that it expands the functionality of said radiator. The radiator (1) comprises a metal plate (1.1), a fluid inlet (8.1), and a fluid outlet (8.2). The radiator (1) receives water from the water circuit of the building through the fluid inlet (8.1), while the fluid is returned to the water circuit through the fluid outlet (8.2).

[0114]The thermal retrofitting system (100) comprises a frame (4) and one or more thermoelectric devices (5) that are po...

Claims

1. A thermal retrofitting system (100) for a radiator (1) located in a room at room temperature, wherein the radiator (1) is adapted to receive a heat transfer fluid through a fluid inlet (8.1) of said radiator (1), wherein the radiator (1) is connected to a reversible heat pump; wherein the thermal retrofitting system (100) comprises: - a frame (4) adapted to be coupled to the radiator (1); and - one or more thermoelectric devices (5) configured to be housed in said frame (4), wherein each of the one or more thermoelectric devices (5) comprise two faces: ∘ a first face configured to be in thermal contact with the radiator (1), said first face being proximal to the radiator (1); and ∘ a second face, opposite the first face, which is configured to be in thermal contact with the frame (4), said second face being proximal to the frame (4); and - one or more fans (2) configured to be housed in the frame (4); - a thermovalve (3) adapted to be arranged in a fluid inlet (8.1) of the radiator (1); - a heat transfer fluid flow control module (8) configured to operate the thermovalve (3) and to set the flow rate of heat transfer fluid entering through the fluid inlet (8.1) of the radiator (1); - a processing and regulating unit (11) configured to communicate with the reversible heat pump and with the heat transfer fluid flow control module (8); wherein the processing and regulating unit (11) is configured to activate the reversible heat pump in a heating mode when the room temperature of the room is lower than a setpoint temperature to be reached and to activate the heat transfer fluid flow control module (8), and said heat transfer fluid flow control module (8) is configured to open the thermovalve completely and to set the maximum flow rate of water available in the radiator (1) as long as the setpoint temperature is not reached.

2. The thermal retrofitting system (100) according to the preceding claim, wherein the heat transfer fluid flow control module (8) is configured to provide values of the flow rate of the heat transfer fluid entering the radiator (1) of between 300 and 1000 l / hour.

3. The thermal retrofitting system (100) according to any of the preceding claims, further comprising: - a control module (9) for the fans (2) configured to operate the fans (2) and to establish the range of revolutions of said fans; wherein the processing and regulating unit (11) is configured to communicate with the control module (9) for the fans (2) and to activate said control module (9) when the room temperature of the room is lower than a setpoint temperature if at least one preestablished heating ramp is not reached after a first predetermined time from the activation of the heat pump in the heating mode and the opening of the thermovalve (3) has elapsed.

4. The thermal retrofitting system (100) according to claim 3, wherein: - the control module (9) for the fans (2) is further configured to increase the range of revolutions of said fans (2) every first predetermined time if the heating ramp is not reached.

5. The thermal retrofitting system (100) according to claims 3 or 4, wherein: - the control module (9) for the fans (2) is configured to establish the range of revolutions of between 400 and 1500 rpm; - the preestablished heating ramp is 0.5°C / h; - the first predetermined time is 0.25 h; and / or - the increase in the range of revolutions of the fans (2) every first predetermined time is at least 450 rpm.

6. The thermal retrofitting system (100) according to claims 3-5, further comprising: - a power supply module (10) for the thermoelectric devices (5) configured to provide the supply voltage of the thermoelectric devices (5) and to regulate the supply voltage of the thermoelectric devices (5) as long as the setpoint temperature is not reached; wherein the processing and regulating unit (11) is configured to activate the power supply module (10) for the thermoelectric devices (5) when the room temperature of the room is lower than a setpoint temperature if at least the preestablished heating ramp is not reached after the first predetermined time from the activation of the reversible heat pump in the heating mode and the opening of the thermovalve (3) has elapsed at least twice.

7. The thermal retrofitting system (100) according to any of claims 3-6, wherein: - the processing and regulating unit (11) is configured to activate the reversible heat pump in a cooling mode when the room temperature of the room is higher than the setpoint temperature to be reached, such that the processing and regulating unit (11) is configured to activate the heat transfer fluid flow control module (8), to completely open the thermovalve, and to set the maximum flow rate of water available in the radiator (1) as long as the setpoint temperature is not reached; and - the control module (9) for the fans (2) is configured to operate at the maximum range of revolutions of said fans (2) as long as the setpoint temperature is not reached.

8. The thermal retrofitting system (100) according to the preceding claim, wherein: - the processing and regulating unit (11) is configured to activate the power supply module (10) for the thermoelectric devices (5) when the room temperature of the room is higher than a setpoint temperature if a preestablished cooling ramp is not reached after a second predetermined time from the activation of the reversible heat pump in the cooling mode and the opening of the thermovalve (3) has elapsed.

9. The thermal retrofitting system (100) according to any of the preceding claims, further comprising: - a condensate collection tray (7) adapted to be arranged in the lower portion of the radiator (1).

10. The thermal retrofitting system (100) according to any of the preceding claims, further comprising: the reversible heat pump and / or the one or more radiators (1).

11. The thermal retrofitting system (100) according to any of the preceding claims, further comprising: - one or more presence sensors installed in the room where the radiator (1) is located and communicated with the processing and regulating unit (11) and configured to detect the presence of people inside the room; - a thermostat configured to establish a setpoint temperature to be reached in the room, said thermostat being communicated with the processing and regulating unit (11).

12. The thermal retrofitting system (100) according to any of the preceding claims, further comprising: - one or more environmental humidity sensors installed in the room where the radiator (1) is located, configured to measure the relative humidity in said room.

13. The thermal retrofitting system (100) according to claims 9 and 12, wherein the processing and regulating unit (11) is configured to activate the power supply module (10) for the thermoelectric devices (5) based on the relative humidity in the room and the amount of condensates in the condensate tray (7).

14. The thermal retrofitting system (100) according to any of the preceding claims, further comprising mechanical fastening means (6) adapted to attach the frame (4) to one of the thermoelectric devices (5) and to the radiator (1), wherein said fastening means (6) in turn comprise: - a radiator anchoring (6.1) and a frame anchoring (6.2) surrounding the thermoelectric device (5); wherein the radiator anchoring (6.1) is arranged on the first face of the thermoelectric device (5) and the frame anchoring (6.2) is arranged on the second face of the thermoelectric device (5); - a screw (6.3) going through the frame (4), the radiator anchoring (6.1), the frame anchoring (6.2), and one of the thermoelectric devices (5), - one or more washers (6.3.1, 6.3.2) arranged at the ends of the screw (6.3).

15. The thermal retrofitting system (100) according to any of claims 1-13, further comprising magnetic fastening means adapted to fix each of the thermoelectric devices (5) between the frame (4) and the radiator (1), preferably wherein the magnetic fastening means comprise two neodymium magnets arranged on the frame (4) and the radiator (1), respectively, surrounding each of the thermoelectric devices (5).

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