Anti-condensation control method for a radiation refrigeration unit

Abstract

This invention specifically relates to an anti-condensation control method for radiant cooling units, comprising two parts: general anti-condensation control and special nighttime control. General anti-condensation control includes start-up protection control, shutdown protection control, and main unit-slave unit linked forced dehumidification control. When Tf ≤ Td max There is a risk of condensation on the ground. Turn off the water system's radiant cooling mode and turn on the air conditioner's dehumidification mode. When Tf > Td max +1, the risk of ground condensation is eliminated, the water system's radiant cooling mode is activated, and the air conditioner's dehumidification mode is deactivated; timed dehumidification is performed at night. During the first period of the night, the air conditioner automatically turns on dehumidification, with a target humidity of A%. If the room humidity is below A%, control is deactivated; during the second period of the night, the target humidity is automatically adjusted to B%, and this adjustment is maintained for at least a certain period, keeping the indoor environment at a lower humidity level, thus reducing the risk of condensation. The control method is highly flexible and timely, ensuring the stability and reliability of the system operation.

Description

Technical Field

[0001] This invention relates to the technical field of radiant cooling systems for multi-split air conditioning units, specifically a method for preventing condensation in radiant refrigeration units. Background Technology

[0002] Radiant cooling systems rely on low-temperature heat exchange surfaces, primarily using radiation for heat exchange, similar in principle to underfloor heating systems. However, during cooling, the low-temperature radiant heat exchange surfaces are prone to condensation in high-humidity environments. For multi-split radiant cooling units with both air-cooled and water-cooled refrigerant systems, condensation on the floor poses a risk of slipping and injury. Frequent condensation also shortens the lifespan of flooring and increases indoor humidity, negatively impacting the user experience. Whether condensation occurs on the radiant surface of a radiant cooling system depends on the air dew point temperature and the surface temperature. The dew point temperature varies with ambient temperature and humidity, while the surface temperature changes depending on the refrigerant flow rate. Current technology for condensation control is rather crude. For example, some rooms have the water system on while others don't. Rooms without radiant cooling mode lack condensation control, yet in practice, the floor in those rooms without radiant cooling can still be affected by the systems in other rooms, posing a condensation risk. Water modules are typically located in condensation-prone areas, while areas further away are less prone to condensation. Current control methods don't consider the need for differentiated control between condensation-prone and non-condensation-prone areas, making them unsuitable for general control. During sleep at night, the requirements for condensation control are even higher, and users cannot monitor the system's operating status, hindering precise control for normal and efficient operation, thus impacting performance and user experience. Summary of the Invention

[0003] The purpose of this invention is to provide a method for preventing condensation in radiant cooling units, which solves the problems of existing radiant cooling systems being unable to flexibly and accurately detect ambient temperature and humidity and radiant surface temperature, and having to rely on forced dehumidification to ensure no condensation, resulting in inflexible control and energy consumption.

[0004] The present invention provides an anti-condensation control method for radiant chiller units, the method comprising start-up operation protection control, shutdown operation protection control, and main unit-slave unit linked forced dehumidification control. The start-up operation protection control method is used when the radiant chiller unit is running, and when Tf ≤ Td... max There is a risk of condensation on the ground. Turn off the water system's radiant cooling mode and turn on the air conditioner's dehumidification mode for at least the initial time. When Tf > Td max +1, the risk of ground condensation is eliminated, turn on the water system radiant cooling mode and turn off the air conditioner dehumidification mode; The shutdown operation protection control method involves detecting that the radiant cooling unit is not turned on and that Tf ≤ Td in the room. max And continue for a second time, turning on the air conditioner to dehumidify and locking the forced dehumidification for a time no less than the first time, when Tf > Td max +1, the risk of ground condensation is eliminated, the air conditioner dehumidification mode is turned off and forced dehumidification is unlocked, and the radiant cooling unit is restored to the off state; The main unit and slave unit linked forced dehumidification control method allows users to configure the radiant cooling unit system, designating the air conditioner installed in the condensation-prone area as the main unit and the air conditioners in other areas as slave units. This provides focused condensation protection for the condensation-prone areas. The main unit is set with a target dew point temperature Td. 目标 When any slave unit is running in radiative cooling mode, the Td of the area where the host is located is monitored, collected, and calculated in real time. max When Td max ≥Td 目标 For a period of time no less than the third time interval, the main unit will automatically forcefully activate the dehumidification mode and lock the forced dehumidification for a period of time no less than the first time interval, until Td. max≤ Td 目标 -1, Turn off the main unit's dehumidification mode and unlock forced dehumidification. Among them, Td max Tf is the maximum dew point temperature, and Tf is the ground temperature.

[0005] Preferably, the method further includes a nighttime anti-condensation control method, which involves timed dehumidification at night. During the first time period at night, the air conditioner automatically turns on dehumidification with a target humidity of 55%. Dehumidification control is activated when the room humidity is above 55% and deactivated when the room humidity is below 50%. During the second time period at night, the target humidity is automatically adjusted to 68%. Dehumidification control is activated when the room humidity is above 68% and deactivated when the room humidity is below 62%.

[0006] Preferably, the first time is 15 minutes.

[0007] Preferably, the second time is 10 minutes.

[0008] Preferably, the third time is 60 seconds.

[0009] Compared with the prior art, the beneficial effects of the present invention are: Multiple anti-condensation control methods form a condensation protection system that can effectively prevent ground condensation under various conditions. The control methods are highly flexible and timely, ensuring the stability and reliability of system operation. Attached Figure Description

[0010] Figure 1 This is a flowchart illustrating typical anti-condensation control measures in the embodiments; Figure 2 This is a layout diagram of the integrated temperature and humidity sensor used in an embodiment. Detailed Implementation

[0011] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Example

[0012] Whether condensation forms on the ground depends on whether the ground temperature is lower than the air dew point temperature. When the ground temperature is too low or the indoor air humidity is too high, the ground temperature will be lower than the air dew point temperature, resulting in condensation.

[0013] This embodiment provides an anti-condensation control method for a radiant cooling unit. This method consists of two parts: normal anti-condensation control and special nighttime control. Normal anti-condensation control remains active as long as the system is running, through continuous real-time monitoring of four integrated environmental temperature and humidity sensors (see reference). Figure 2 A ground temperature sensor and a dew point temperature sensor control the opening and closing of the water system. The opening and closing of the water system refers to the control of electric two-way valves. The water module of the water system is connected to a water distributor, which in turn connects to water pipes under the floors of each room. Electric two-way valves are installed on these water pipes. By controlling the opening and closing of each electric two-way valve, the radiant cooling mode of each room is switched on and off, thereby controlling the ground temperature and anticipating the risk of condensation. If necessary, it will also force the indoor unit of the air conditioner to start dehumidification for system protection, achieving the goal of lowering the dew point temperature. Special nighttime control uses a pre-timed dehumidification method to reduce indoor humidity before the nighttime sleep period, ensuring no risk of condensation during sleep. Simultaneously, the target humidity for the sleep period is lowered to ensure the air conditioner dehumidification can operate normally at night, further reducing the risk of condensation.

[0014] Specifically, refer to Figure 1 The method typically includes anti-condensation control including start-up protection control, shutdown protection control, and main unit-sub-unit linkage forced dehumidification control. The start-up protection control, shutdown protection control, and main unit-sub-unit linkage forced dehumidification control are always in effect during system operation.

[0015] The start-up protection control method is used when the radiant chiller unit is running, and Tf≤Td maxThere is a risk of condensation on the ground. Turn off the water system's radiant cooling mode to prevent further drop in ground temperature. Turn on the air conditioner's dehumidification mode to reduce indoor humidity and maintain this for at least 15 minutes. After 15 minutes, reassess for condensation risk. If condensation is present, continue dehumidification until Tf > Td. max +1, the risk of ground condensation is eliminated, turn on the water system radiant cooling mode and turn off the air conditioner dehumidification mode.

[0016] The shutdown operation protection control refers to the situation where, when using the radiant cooling unit, the user may only operate the unit in one or some rooms, while the rooms not in operation are protected against condensation by the shutdown operation protection control. The method involves detecting whether the temperature difference (Tf) in the rooms where the radiant cooling unit is not operating is less than or equal to the temperature difference (Td). max Continue for 10 minutes, then turn on the air conditioner to dehumidify and lock the forced dehumidification for at least 15 minutes. After 15 minutes, check again for condensation risk. If there is a risk of condensation, continue dehumidification until Tf > Td. max +1, the risk of ground condensation is eliminated, the air conditioner dehumidification mode is turned off and forced dehumidification is unlocked, and the radiant cooling unit is restored to the off state.

[0017] The main unit and slave unit linked forced dehumidification control method allows users to configure the radiant cooling unit system, designating the air conditioner installed in the condensation-prone area as the main unit and the air conditioners in other areas as slave units. This provides focused condensation protection for the condensation-prone areas. The main unit is set with a target dew point temperature Td. 目标 When any slave unit is running in radiative cooling mode, the Td of the area where the host is located is monitored, collected, and calculated in real time. max When Td max ≥Td 目标 If the humidity remains at least 60 seconds, the main unit will automatically force the dehumidification mode to start and lock the dehumidification for at least 15 minutes, until Td. max≤ Td 目标 -1, turn off the main unit's dehumidification mode and unlock forced dehumidification.

[0018] Among them, Td max Tf is the maximum dew point temperature, and Tf is the ground temperature.

[0019] The method also includes a nighttime anti-condensation control method, which involves timed dehumidification at night. During the first time period at night (e.g., 8:00 PM - 10:00 PM), the air conditioner automatically turns on dehumidification with a target humidity of 55%. Dehumidification control is activated when the room humidity is above 55% and deactivated when the room humidity is below 50%. After pre-dehumidification during this period, the overall environment is relatively dry, and the dew point temperature is much lower than the floor temperature, which can greatly eliminate the risk of nighttime condensation. Even if the humidity slowly increases under the influence of indoor and outdoor moisture sources, it will not lead to excessive humidity and condensation, ensuring the reliability of the system operation at night. During the second time period at night (e.g., the sleep period from 10:00 PM to 7:00 AM the next day), the target humidity is 68%. Dehumidification control is activated when the room humidity is above 68% and deactivated when the room humidity is below 62%.

[0020] The daytime dehumidification control method, which is the opposite of nighttime dehumidification, is as follows: the target humidity can be adjusted in the range of 55%-65% (default 65%). Dehumidification control is turned on when the room humidity is greater than the target humidity +3%, and de-controlled when the room humidity is lower than the target humidity -3%.

[0021] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for preventing condensation control in a radiant cooling unit, characterized in that, The method includes start-up protection control, shutdown protection control, and main unit-sub-unit linked forced dehumidification control. The start-up protection control method is used when the radiant chiller unit is running, and Tf ≤ Td. max There is a risk of condensation on the ground. Turn off the water system's radiant cooling mode and turn on the air conditioner's dehumidification mode for at least the initial time. When Tf > Td max +1, the risk of ground condensation is eliminated, turn on the water system radiant cooling mode and turn off the air conditioner dehumidification mode; The shutdown operation protection control method involves detecting that the radiant cooling unit is not turned on and that Tf ≤ Td in the room. max And continue for a second time, turning on the air conditioner to dehumidify and locking the forced dehumidification for a time no less than the first time, when Tf > Td max +1, the risk of ground condensation is eliminated, the air conditioner dehumidification mode is turned off and forced dehumidification is unlocked, and the radiant cooling unit is restored to the off state; The main unit and slave unit linked forced dehumidification control method allows users to configure the radiant cooling unit system, designating the air conditioner installed in the condensation-prone area as the main unit and the air conditioners in other areas as slave units. This provides focused condensation protection for the condensation-prone areas. The main unit is set with a target dew point temperature Td. 目标 When any slave unit is running in radiative cooling mode, the Td of the area where the host is located is monitored, collected, and calculated in real time. max When Td max ≥Td 目标 For a period of time no less than the third time interval, the main unit will automatically forcefully activate the dehumidification mode and lock the forced dehumidification for a period of time no less than the first time interval, until Td. max ≤Td 目标 -1, Turn off the main unit's dehumidification mode and unlock forced dehumidification. Among them, Td max Tf is the maximum dew point temperature, and Tf is the ground temperature.

2. The anti-condensation control method for a radiant cooling unit according to claim 1, characterized in that, The method also includes a nighttime anti-condensation control method, which involves timed dehumidification at night. During the first time period at night, the air conditioner automatically turns on dehumidification with a target humidity of 55%. Dehumidification control is activated when the room humidity is above 55% and deactivated when the room humidity is below 50%. During the second time period at night, the target humidity is automatically adjusted to 68%. Dehumidification control is activated when the room humidity is above 68% and deactivated when the room humidity is below 62%.

3. The anti-condensation control method for a radiant cooling unit according to claim 1, characterized in that, The first time is 15 minutes.

4. The anti-condensation control method for a radiant cooling unit according to claim 1, characterized in that, The second time is 10 minutes.

5. The anti-condensation control method for a radiant cooling unit according to claim 1, characterized in that, The third time is 60 seconds.

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