Monitoring and / or adapting an operation of a pump of a domestic hot water system

Abstract

The invention relates to a method (10) for monitoring and / or adapting an operation of a pump (40) of a domestic hot water system (20). The method (10) comprises the steps of: activating (11) the pump (40) to circulate water through the hot water system (20); measuring (12) a temperature increase of the water in the domestic hot water system (20) in discrete time or temperature steps after the activation of the pump (40); determining (13) at least one parameter, wherein the at least one parameter comprises: a time required for reaching a steady state temperature after the activation of the pump (40), and / or an estimated system temperature of the domestic hot water system (20) at the steady state. The method (10) comprises the further step of: forwarding (14) the at least one parameter via a communication interface (44) of the pump (40), and / or adapting a pump setting of the pump (40) based on the at least one parameter.

Description

[0001] MONITORING AND / OR ADAPTING AN OPERATION OF A PUMP OF A DOMESTIC HOT WATER SYSTEM

[0002] TECHNICAL FIELD OF THE INVENTION

[0003] The invention relates to a method for monitoring and / or adapting an operation of a pump of a domestic hot water system. The invention further relates to a pump for use in a domestic hot water system.

[0004] BACKGROUND OF THE INVENTION

[0005] A domestic hot water system delivers hot water via pipes to various fixtures in a building, such as sinks, showers or other appliances. If no hot water is withdrawn from the system for a longer amount of time, the water in the pipes cools down. If there is an extensive piping, it may take a relatively long amount of time to replace this cooled down water with hot water from a hot water supply (e.g. , a boiler) , which can cause long waiting times at a tap and waste of water.

[0006] If provided with recirculation pipe, circulation pumps can be used to generate a flow inside the pipes of the system and to circulate the water back to a heat source (e.g. , the boiler) , even if no hot water is withdrawn. This ensures that the water in the pipes is always relatively hot and the waiting time for hot water is reduced.

[0007] Ideally, the configurations and settings of such a circulation pump (e.g. , runtime, flow rate etc. ) should be adapted to the individual hot water system (e.g. , dimension of the piping, temperature of boiler, etc. ) . This is often done by manual calculations . However , it is dif ficult to provide and / or calculate accurate information about a domestic hot water system and to determine the optimal pump settings in this way .

[0008] Thus , it is an obj ective to provide an improved pump for a domestic hot water system and an improved method for monitoring and / or adapting an operation of such a pump which avoid the above-mentioned di sadvantage s .

[0009] SUMMARY OF THE INVENTION

[0010] The obj ect of the present invention is achieved by the solution provided in the enclosed independent claims . Advantageous implementations of the present invention are further defined in the dependent claims .

[0011] According to a first aspect , the invention relates to a method for monitoring and / or adapting an operation of a pump of a domestic hot water system . The method comprises the steps of : activating the pump to circulate water through the hot water system; mea suring a temperature increase of the water in the domestic hot water system in di screte time or temperature steps after the activation of the pump ; determining at least one parameter , wherein the at least one parameter comprises : a time required for reaching a steady state temperature after the activation of the pump , and / or an estimated system temperature of the domestic hot water system at the steady state . The method further comprises the step of : forwarding the at least one parameter via a communication interface of the pump , and / or adapting a pump setting of the pump based on the at least one parameter . This achieves the advantage of that the pump can be configured and / or adapted to a specific domestic hot water system in an efficient way. For instance, this can reduce the efforts during an installing and / or commissioning of the pump, when attempting to provide the most efficient operation for the individual installation .

[0012] The at least one parameter or information derived from the parameter can be used internally by other control algorithms of the pump, e.g. , for determining the optimal recirculation times. However, the at least one parameter can also be accessible to an installer of the pump and / or of the system, e.g. , for troubleshooting, configuring, and / or commissioning of the pump and / or the system.

[0013] The (estimated) system temperature may refer to an estimated average temperature of the water throughout the hot water system (e.g. , between a hot water supply and the pump) . For instance, at steady state, this temperature is expected to be somewhat smaller than a temperature measured directly at the pump due to heat loss effects and / or expected temperature differentials in the hot water system.

[0014] The estimated temperature could differ from the actual media temperature, due to several factors such as delay, offset error, etc .

[0015] With continuous recirculation the delta temperature across the entire system is low - depending on the heat-loss. Theoretically, the average system temperature would be higher than the temperature at the pump. The system temperature is measured / estimated directly at the pump and i s not an average of the system temperature . If anything , the temperature at the pump should be lower than any other place before the pump .

[0016] The pump can be a circulation pump or a recirculation pump . The pump can also be a water transfer pump .

[0017] The pump may comprise a pump body which is connected to a piping of the domestic hot water system, in particular to a hot water recirculation line . For example , the pump is arranged downstream of all consumers and / or f ixtures for extracting hot water f rom the system .

[0018] The temperature increase can be measured in or at the pump .

[0019] In an embodiment , the temperature increase is measured in a water carrying element of the pump , and / or the temperature increase is measured in a hot water recirculation line of the domestic hot water system .

[0020] Preferably, the temperature increase is measured downstream of all consumers and / or fixture s in the system, in particular of all consumers and / or f ixtures for extracting hot water from the system .

[0021] In an embodiment , the pump is activated for a fixed amount of time and / or with a fixed flowrate .

[0022] For example , the water temperature is mea sured at the end of the fixed amount of time . This measurement can be used as the steady state temperature . In an embodiment, the estimated system temperature is determined based on the discrete temperature measurements and / or based on the measured temperature of the water at the steady state.

[0023] For instance, the estimated system temperature is calculated by feeding the discrete temperature values to a mathematical model (e.g. , by fitting a curve to the temperature value) .

[0024] Alternatively, the system temperature can be estimated as the temperature measured at steady state or a fraction thereof.

[0025] In an embodiment, the at least one parameter is forwarded to an external user device, to a central database and / or to a server.

[0026] In an embodiment, the method comprises the further step of: estimating a heat loss of the domestic hot water system by comparing the estimated system temperature with an expected or known supply temperature of a hot water supply of the domestic hot water system.

[0027] For instance, a known flow rate can be considered when estimating the heat loss .

[0028] The hot water supply may comprise a hot water supply line and / or a hot water production system, such as a boiler, a tank and / or a heat exchanger.

[0029] In an embodiment, the method is carried out when the pump operates in an analysis mode.

[0030] For example, the pump is set to the analysis mode in regular time intervals (e.g. , every 25thhour) and / or when receiving a respective control command, e.g. , via the communication interface of the pump. The pump can be set to the analysis mode during a commissioning of the pump.

[0031] In an embodiment, the pump is operable in a normal operating mode in which the pump is regularly or irregularly activated for a pre-set runtime and / or deactivated for a pre-set off-time; wherein the step of adapting the pump setting comprises adjusting the runtime and / or adjusting the off-time of the pump.

[0032] For example, in the normal operating mode, the pump is regularly or irregularly activated for the pre-set runtime and / or deactivated for the pre-set off-time based on a schedule.

[0033] For instance, in normal operating mode the pump can be alternately activated for the runtime and deactivated for the of f -time .

[0034] In particular, the normal operating mode is different to the analysis mode. In the normal operating mode (which may also be referred to as: recirculation mode) , the pump can be activated in regular time intervals for the runtime to recirculate the water in the system (i.e. , replace the cooled down water in the system with "new" hot water from a hot water supply) .

[0035] The runtime and the off-time can be stored in a memory of the pump .

[0036] In an embodiment, the runtime is set to the time required for reaching the steady state.

[0037] This achieves the advantage that the runtime in normal mode is long enough to guarantee a sufficient recirculation of the water in the system.

[0038] In an embodiment, the off-time is adjusted based on the determined heat loss.

[0039] This achieves the advantage that the water in the system does not cool down below a certain temperature when the pump is not running .

[0040] In addition, the knowledge of a flow rate in the domestic hot water system can be considered when adjusting the off-time.

[0041] In an embodiment, the method comprises the further step of: issuing an alarm or a notification if the estimated system temperature exceeds a first temperature threshold and / or falls below a second temperature threshold.

[0042] In an embodiment, the alarm or the notification is indicated on a display or an indicator element of the pump, and / or the alarm or the notification is forwarded via the communication interface to an external device.

[0043] This achieves the advantage that an installer can be informed if the pump does not manage to keep the temperature in the system within a certain range.

[0044] According to a second aspect, the invention relates to a pump, in particular a circulation pump, for a domestic hot water system, wherein, when activated, the pump is configured to circulate water through the hot water system. The pump comprises a temperature sensor which is configured to measure a temperature increase of the water in discrete time or temperature steps after the activation of the pump; wherein the pump further comprises a processing unit which is configured to determine at least one parameter, wherein the at least one parameter comprises: a time required for reaching a steady state temperature after the activation of the pump, and / or an estimated system temperature of the domestic hot water system at the steady state. The processing unit is further configured to forward the at least one parameter via a communication interface of the pump, and / or to adapt a pump setting of the pump based on the at least one parameter.

[0045] For example, the temperature sensor is configured to measure the temperature increase in discrete time or temperature steps after the activation of the pump when the pump operates in an analysis mode .

[0046] In an embodiment, the pump is further operable in a normal operating mode in which the pump is regularly or irregularly activated for a pre-set runtime and / or deactivated for a preset off-time, e.g. , based on a schedule. The adaption of the pump setting may comprise an adjustment of the runtime and / or an adjustment of the off-time of the pump.

[0047] In particular, the temperature sensor is mounted to be in contact with the water. Alternatively, the temperature sensor is not in direct contact with the water. The sensor / s may be mounted e.g. inside the control box of the pump.

[0048] In an embodiment, the temperature sensor is mounted in and / or on a water carrying element of the pump, and / or the temperature sensor is mounted in a hot water recirculation line of the domestic hot water system.

[0049] For example, the temperature sensor is mounted in and / or on a water pipe directly in front of or behind the pump relative to a flow direction of the water.

[0050] In an embodiment, the communication interface is a wireless interface, such as a Bluetooth or a WiFi interface.

[0051] The above description with regard to the method according to the first aspect of the invention is correspondingly valid for the pump according to the second aspect of the invention.

[0052] According to a third aspect, the invention relates to a domestic hot water system, comprising: the pump according to the second aspect of the invention; and a hot water recirculation line which is connected to the pump.

[0053] The domestic hot water system can be a residential or a commercial domestic hot water system.

[0054] BRIEF DESCRIPTION OF THE DRAWINGS

[0055] The invention will be explained in the following together with the figures.

[0056] Fig. 1 shows a flow chart of a method for monitoring and / or adapting an operation of a pump of a domestic hot water system according to an embodiment;

[0057] Fig. 2 shows a measured temperature increase in a domestic hot water system according to an embodiment; Fig. 3 shows a schematic diagram of a domestic hot water system according to an embodiment; and

[0058] Fig. 4 shows a schematic diagram of a pump for a domestic hot water system according to an embodiment.

[0059] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0060] Fig. 1 shows a flow chart of a method 10 for monitoring and / or adapting an operation of a pump of a domestic hot water system according to an embodiment.

[0061] The method 10 comprises the steps of: activating 11 the pump to circulate water through the hot water system; measuring 12 a temperature increase of the water in the domestic hot water system in discrete time or temperature steps after the activation 11 of the pump; determining 13 at least one parameter, wherein the at least one parameter comprises: a time required for reaching a steady state temperature after the activation of the pump, and / or an estimated system temperature of the hot water system at the steady state. The method 10 further comprises the step of: forwarding 14 the at least one parameter via a communication interface of the pump, and / or adapting a pump setting of the pump based on the at least one parameter .

[0062] The pump can be a circulation pump or a recirculation pump. The pump can also be a water transfer pump.

[0063] The steps of determining 13 the at least one parameter can be carried out by a processing unit (e.g. , a microprocessor) of the pump and / or by an external computing device.

[0064] For instance, the processing unit or the external computing device thereby executes an algorithm which comprises an internal media temperature estimator for estimating the system temperature (Tsys) and / or a specific analysis sequence to obtain an estimation of the hot water 'recirculation time' (trec) • The recirculation time trecof the domestic hot water system (also: hot water recirculation system) can be obtained at the point at which the media temperature reaches the maximum steady-state temperature. In other words, the determined time required for reaching a steady state can be estimated as the recirculation time of the system.

[0065] The temperature increase can be measured by a temperature sensor within or on a fluid transporting component of the pump or within or on a water pipe of the system close to the pump.

[0066] Fig. 2 shows an example of a temperature increase of the water measured in discrete temperature steps after activation 11 of the pump .

[0067] When carrying out the method 10, the pump can be activated 11 for a fixed amount of time (i.e. , a fixed runtime or activation time) and / or with a fixed flowrate. In the example shown in Fig. 2, the fixed runtime is 900 s and the fixed flowrate is 1 GPM.

[0068] During the fixed runtime, an internal media temperature estimate can be tracked by measuring the temperature of the hot water in discrete temperature steps. This information can be used for determining the recirculation time from a heat source of the hot water system to the pump. Typically, the pump is located at the end of a recirculation pipe of the hot water system (e.g. , downstream of all consumers and fixtures for extracting hot water and close to the heat source) . In Fig. 2, AT is the temperature discretization for updating the timestamps of the temperature measurement.

[0069] The estimated system temperature can be determined 13 based on the discrete temperature measurements and / or based on the measured temperature of the water at the steady state.

[0070] For instance, the system temperature can be estimated based on a temperature measurement at the end of the activation time. In this case, the system temperature can be estimated as a fraction of the measured steady state temperature or as the steady state temperature .

[0071] Alternatively, the system temperature could also be estimated based on the discrete temperature measurements using a mathematical model (e.g. , fitting a curve to the temperature measurements as shown in Fig. 2) .

[0072] The system temperature may be used for heat loss approximations and system monitoring, e.g. if the system temperature is too low, an alarm may be raised.

[0073] The method 10 can be carried out when the pump operates in an analysis mode. For instance, this analysis mode may be referred to as "comfort level check".

[0074] For example, the analysis mode (and thus the method 10) can be activated automatically according to a schedule (e.g. , every 25thhour) or manually by an installer, e.g. , via a dedicated app on an external user device which communicates with the pump. The scheduled activation could primarily be for internal algorithm and continuous system monitoring use, whereas the manual activation could be done by the installer during a troubleshooting, configuring and / or commissioning the domestic hot water system.

[0075] The pump can further be operable in a normal operating mode in which the pump is regularly or irregularly activated for a preset runtime and / or deactivated for a pre-set off-time, e.g. based on a schedule. The schedule may define the on-times and off-times of the pump in the normal operating mode. Adapting 14 the pump setting may comprise adjusting this runtime and / or adjusting this off-time of the pump.

[0076] The pump can forward 14 the at least one parameter or information derived from the at least one parameter to the external user device, to a central database and / or to a server via its communication interface.

[0077] For instance, the external user device can be a smartphone running the dedicated app which processes and / or displays information based on the at least one parameter.

[0078] The method 10 utilizes the advantage of having a temperature sensor and using the information this sensor provides to obtain an understanding / estimation of certain system parameters that are essential for providing an accurate control of the recirculation in the hot water system (in particular, of the pump) . For instance, pump settings and configurations can be adapted based on the results of these temperature measurements. The temperature sensor can be a built-in sensor or an external temperature sensor with well-known characteristics

[0079] The adaption / configuration of the pump based on the determined parameters can be carried out manually by an installer or automatically, e.g. by a hot water recirculation control algorithm.

[0080] Fig. 3 shows the domestic hot water system 20 according to an embodiment .

[0081] The domestic hot water system 20 can comprise a hot water supply, such as a supply line and / or a hot water production system 22 (e.g. a boiler, a heat tank or a heat exchanger) . The hot water supply can supply hot water to a hot water recirculation line 21 from which several fixtures 23 (i.e. , consumers) along the line 21, such as sinks, can withdraw hot water. After passing the fixtures 23, the hot water recirculation line 21 can lead back to the hot water supply.

[0082] The pump 40 can be arranged on and / or connected to the hot water recirculation line 21 downstream of the fixtures 23 (e.g., downstream of location B in Fig. 3) , and can be configured to circulate the hot water back to the production system 22.

[0083] The system 20 may further comprise a cold water supply line 24 and a return line.

[0084] The domestic hot water system 20 can be a residential or a commercial domestic hot water system.

[0085] The pump 40 can be operated in a normal operating mode (or recirculation mode) in which the pump is e.g. alternately activated for a pre-set runtime and deactivated for a pre-set off-time (e.g. , based on a schedule) .

[0086] The activation of the pump 40 in normal operating mode could also be triggered by a signal which is, e.g. , issued if the temperature in the system has dropped below of certain value.

[0087] In this normal operating mode (which is different to the analysis mode) , the pump can fulfill its main function of (regularly) replacing cooled down water in the recirculation line 21 with hot water from the hot water supply (e.g. , from the production system 22) . The pre-set runtime and off-time can be stored in a memory of the pump.

[0088] The step of adapting 14 the pump setting can comprise adjusting the runtime and / or adjusting the off-time (of the normal operating mode) based on the at least one parameter determined 13 during analysis mode.

[0089] For instance, the approximation of the recirculation time (i.e. , the time from A to C in Fig. 3) during analysis mode allows for increasing an accuracy of the pump runtime setting in normal operating mode. A processing unit of the pump could execute an algorithm that automatically obtains this information and uses it for setting the pump runtime. Thereby, for instance, the runtime of the pump 40 (in normal operating mode) can be set to the time required for reaching the steady state which was determined during analysis mode.

[0090] In one example, in analysis mode the pump approximates a time 2 minutes for reaching a steady state temperature. The pump 40 can then set the pump ON time (i.e. , the runtime in normal mode) to be at least 2 minutes, thereby ensuring that when the pump turns on for this ON time, the hot water from the heat source (e.g. , hot water supply) will be transported from A to C in Fig. 3.

[0091] In another example, in analysis mode the pump approximates a time of 2 minutes for reaching a steady state temperature. This information can be provided to an installer who wishes to install the pump with a timer-based control. For instance, the information can be forwarded to a communication device of the installer (e.g. , a smartphone running a dedicated app) via the communication interface of the pump. The installer can then configure the pump ON time (i.e. , the runtime in normal mode) to be at least 2 minutes, thereby ensuring that when the pump turns on for this ON time, the hot water from the heat source has been transported from A to C in Fig. 3.

[0092] The method 10 may further comprise the optional step of: estimating 15 a heat loss of the hot water system 20 by comparing the estimated system temperature with an expected or known supply temperature of the hot water supply of the hot water system 20. Thereby, also the knowledge of a flow rate in the system can be considered. This heat loss estimation can also be carried out in analysis mode.

[0093] This allows for estimating the time it takes for the recirculation line 21 to cool to a specific temperature when the pump is not running.

[0094] For instance, the off-time (in normal operating mode) can be adjusted based on this determined heat loss. The off-time can be chosen such that the system temperature does not cool down below a minimum temperature value .

[0095] The estimated system temperature furthermore allows for raising various warnings, and / or for informing or calling for action from a user.

[0096] For instance, the method 10 may comprise the further step of: issuing 16 an alarm or a notification if the estimated system temperature exceeds a first temperature threshold and / or falls below a second temperature threshold.

[0097] The alarm or the notification can be indicated on a display or an indicator element of the pump. In addition or alternatively, the alarm or the notification can be forwarded via the communication interface to an external device.

[0098] In one example, the pump 40 approximates a system temperature of 52 °C in analysis mode. Comparing the system temperature with the expected supply temperature combined with the knowledge of a constant flow of e.g. 1 GPM (when activating the pump in analysis mode and / or in normal operating mode) , allows for approximating the heat loss during this specific condition of the system. This heat loss allows for calculating an estimated (ideal) pump OFF time in normal operating mode.

[0099] In another example, the pump 40 approximates a system temperature of 35°C in analysis mode. The pump 40 can be configured to operate based on a minimum temperature set point of 39 °C. The result of the system temperature estimation may indicate that the system is not capable of reaching the desired temperature. As a consequence, an alarm can be raised. Fig . 4 shows a schematic diagram of the pump for use in the domestic hot water system 20 . For example , the pump 40 can be configured to carry out the method 10 as shown in Fig . 1 .

[0100] The pump 40 comprise s a temperature sensor 42 . When activated, the pump 40 is configured to circulate water through the hot water system; wherein the temperature sensor 42 is configured to measure the temperature increa se of the water in the domestic hot water system 20 in dis crete time or temperature steps after the activation of the pump 40 . The pump 40 further comprise s a proces sing unit 43 which is conf igured to determine the at least one parameter , wherein the at least one parameter comprise s : the time required for reaching a steady state temperature after the activation of the pump , and / or the e stimated system temperature of the hot water system at the steady state . The proces sing unit 43 is configured to forward the at least one parameter via the communication interface 44 of the pump 40 , and / or to adapt a pump setting of the pump 40 based on the at least one parameter .

[0101] The temperature sensor 42 can be configured to measure the temperature increase in discrete time or temperature steps after the activation of the pump 40 , in particular , when the pump operates in an analysis mode .

[0102] The pump 40 may further be operable in a normal operating mode in which the pump 40 is regularly or irregularly activated for a pre-set runtime and / or deactivated for a pre- set off-time based on a s chedule ; wherein the adaption of the pump setting comprise s an adj ustment of the runtime and / or an adj ustment of the off-time of the pump 40 .

[0103] The pump 40 can be a circulation pump or a recirculation pump . The pump 40 can also be a water transfer pump.

[0104] In particular, the pump 40 is configured to circulate water through the hot water recirculation line 21 of the domestic hot water system 20. Therefore, the pump 40, in particular the pump body, can be connected to the hot water recirculation line 21 of the system 40, e.g. a hot water pipe of the system.

[0105] The temperature sensor 42 is preferably mounted to be directly or indirectly in contact with the water that is pumped.

[0106] For instance, the temperature sensor 42 is mounted in and / or on a water carrying or transporting element of the pump 40, e.g. within the pump body. For example, the temperature sensor 42 can be arranged in a pump casing or nozzle of the pump.

[0107] However, the temperature sensor 42 can also be mounted in the water pipe of the recirculation line 21, for instance directly in front of or behind the pump 40 relative to a flow direction of the water. For instance, the temperature sensor is mounted in the pipe less than 0.5 m, less than 0.25 m or less than 0.1 m away from the pump body.

[0108] The processing unit 43 can be a microprocessor of the pump. For instance, the processing unit 43 can be a component of the pump electronics. Alternatively the processing unit may be external to the pump. In this case the pump will be provided with a wireless or wirebound interface for communicating with the external processing unit.

[0109] The communication interface 44 can be a wireless interface, such as a Bluetooth or a WiFi interface. The pump 40 can further comprise a display and / or an indicator element 45. The display and / or indicator element 45 can show warning and / or notifications. Further, the display can show the determined at least one parameter.

[0110] In the following, a number of possible use cases of the method 10 and / or the pump 40 are discussed:

[0111] The estimated system temperature obtained from a large number of pumps could be used for future pump design / development and / or for mapping of the systems in which pumps usually operate. For instance, 'xx'% of the pumps operate below 'yy' °C. The information forwarded 14 from a large number of pumps could be gathered on a central server or in a database for evaluation.

[0112] The method 10 could further be used to further analyze the system temperature of specific domestic hot water systems. By performing this analysis in a controlled and known manner, additional information could be retrieved and used to update an internal pump algorithm, in particular to adapt the algorithm which control the steps of the method 10 to match the needs of the system. For instance, if the pump 40 fails to obtain a system temperature of 'xx' °C within the conditions of the method 10 (e.g. , an activation 11 with a flow rate of 'yy' m3 / h for a runtime 'zz' seconds) , the pump 40 could update its controls and carry out the method 10 again. This process could be repeated until the correct settings have been found and these settings could be added to the pump algorithms which carries out steps of the method 10, adjusting them to match the system (such as updating the flow setting of the pump 40) . The method 10 could further be used to provide end-user or installer warnings / alarms . The system temperature can indicate in which conditions the system operates. If the system temperature is too low, it could indicate that the system is lacking comfort or if the system temperature is too high, it could indicate that the system has a reduced efficiency. The estimated system temperature could further be used to provide suggestions / recommendations for updating the system configuration. For instance, if the system temperature is high (e.g. , above 'xx' °C) and could result in a scalding risk at the taps, a resulting recommendation could be to lower the supply temperature to reduce risks of lime and / or scalding.

[0113] Furthermore, the recirculation times received from a large number of pumps could reveal information on the size of the installations in which pumps 40 usually operate. This information could be used to optimize the operation and configurations of current and future algorithms in such pumps 40. The optimization of algorithms would result in an increase in both comfort and efficiency, considering the balance between efficiency and performance become more accurate. For example, a pump algorithm could adapt the hot water recirculation time to optimize the runtime of a pump. If the recirculation time of the system is found to be 'xx' seconds, the pump runtime (in a normal operating mode) could be set to the recirculation time, or the recirculation time could be used in another way to adapt to the specific installation.

[0114] Furthermore, the estimated recirculation time could be implemented into a guided-commissioning process. The estimated recirculation time could be used by the installer during the configuration of the pump. The estimated recirculation time allows the installer to specify the operating pattern of the pump 40 more accurately, thereby increasing the pump efficiency and performance. For example, the recirculation time could be used in a guided-commis sioning of a timer-based control where the installer specifies the ON- and OFF-time of the pump 40 in normal operating mode. In this case the ON-time (i.e. , runtime) could be set to the recirculation time and (combined with a few installer questions) the OFF-time could be approximated as well.

Claims

Claims1. A method (10) for monitoring and / or adapting an operation of a pump (40) of a domestic hot water system (20) , comprising the steps of: activating (11) the pump (40) to circulate water through the hot water system (20) ; measuring (12) a temperature increase of the water in the domestic hot water system (20) in discrete time or temperature steps after the activation of the pump (40) ; determining (13) at least one parameter, wherein the at least one parameter comprises: a time required for reaching a steady state temperature after the activation of the pump (40) , and / or an estimated system temperature of the domestic hot water system (20) at the steady state; forwarding (14) the at least one parameter via a communication interface (44) of the pump (40) , and / or adapting a pump setting of the pump (40) based on the at least one parameter .

2. The pump (40) of claim 1, wherein the temperature increase is measured in or on a water carrying element of the pump (40) , and / or wherein the temperature increase is measured in or on a hot water recirculation line (21) of the domestic hot water system (20) .

3. The method (10) of claim 1 or 2, wherein the pump (40) is activated for a fixed amount of time and / or with a fixed flowrate.

4. The method (10) of any one of the preceding claims, wherein the estimated system temperature is determined based on the discrete temperature measurements and / or based on the measured temperature of the water at the steady state.

5. The method (10) of any one of the preceding claims, wherein the at least one parameter is forwarded to an external user device, to a central database and / or to a server.

6. The method (10) of any one of the preceding claims, further comprising the step of: estimating (15) a heat loss of the domestic hot water system (20) by comparing the estimated system temperature with an expected or known supply temperature of a hot water supply of the domestic hot water system (20) .

7. The method (10) of any one of the preceding claims, wherein the method (10) is carried out when the pump (40) operates in an analysis mode.

8. The method (10) of claim 7, wherein the pump (40) is operable in a normal operating mode in which the pump (40) is regularly or irregularly activated for a pre-set runtime and / or deactivated for a pre-set off-time; wherein the step of adapting (14) the pump setting comprises adjusting the runtime and / or adjusting the off-time of the pump (40) .

9. The method (10) of claim 8, wherein the runtime is set to the time required for reaching the steady state.

10. The method (10) of claim 6 and any one of claims 8 to 9, wherein the off-time is adjusted based on the determined heat loss.

11. The method (10) of any one of the preceding claims, further comprising the step of: issuing (16) an alarm or a notification if the estimated system temperature exceeds a first temperature threshold and / or falls below a second temperature threshold.

12. The method (10) of claim 11, wherein the alarm or the notification is indicated on a display or an indicator element (45) of the pump (40) , and / or wherein the alarm or the notification is forwarded via the communication interface (44) to an external device.

13. A pump (40) , in particular a circulation pump, for a domestic hot water system (20) , wherein, when activated, the pump (40) is configured to circulate water through the hot water system (20) ; wherein the pump comprises a temperature sensor (42) which is configured to measure a temperature increase of the water in the domestic hot water system (20) in discrete time or temperature steps after the activation of the pump (40) ; wherein the pump (40) further comprises or has an interface for communication with a processing unit (43) which is configured to determine at least one parameter, wherein the at least one parameter comprises: a time required for reaching a steady state temperature after the activation of the pump (40) , and / oran estimated system temperature of the domestic hot water system (20) at the steady state; wherein the processing unit (43) is configured to forward the at least one parameter via a communication interface (44) of the pump (40) , and / or to adapt a pump setting of the pump (40) based on the at least one parameter.

14. The pump (40) of claim 13, wherein the temperature sensor (42) is mounted in or on a water carrying element of the pump (40) , and / or wherein the temperature sensor (42) is mounted in or on a hot water recirculation line (21) of the domestic hot water system (20) .

15. The pump (40) of claim 13 or 14, wherein the communication interface (44) is a wireless interface, such as a Bluetooth or a WiFi interface.

16. A domestic hot water system (20) , comprising: the pump (40) of any one of claims 13 to 15; and a hot water recirculation line (21) which is connected to the pump (40) .

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