JP6168958B2 - Hot water apparatus and abnormality notification method in hot water apparatus - Google Patents

Description

  The present invention relates to a technique for detecting clogging of a water circuit in a hot water apparatus.

In the hot water device, the water circulating in the water circuit is heated by the heat source device, and the water circulating in the heated water circuit is stored in the tank, and the water circulating in the primary water circuit is heated by the heat source device. In addition, there is an indirect heating type in which water circulating in the secondary water circuit is heated by water circulating in the primary water circuit, and water circulating in the heated secondary water circuit is stored in a tank.
In some indirect heating types, the primary water circuit is a fluid circuit in which a fluid such as brine other than water circulates.

Patent Document 1 describes a method of detecting clogging of a water circuit due to scale deposition of calcium carbonate or the like in a direct heating type hot water apparatus.
Specifically, Patent Document 1 discloses (1) a method for measuring a change in the flow rate of water in the water circuit, (2) a method for measuring a change in water pressure in the water circuit, and (3) an output of a pump in the water circuit. A method for measuring change and (4) a method for measuring change in heating capacity are described as methods for detecting clogging.

JP 2004-116942 A

  In the method (1), a flow measuring device such as a flow switch or a flow sensor is required to measure the flow rate of water, and in the method (2), a pressure switch or pressure sensor is used to measure the water pressure. Such a pressure measuring device is required. Therefore, adopting the methods (1) and (2) leads to an increase in the cost of the hot water apparatus.

  In the method (2), even when clogging does not occur, if the pressure of water in the water circuit increases due to warming and expansion of water, it may be erroneously detected that clogging has occurred. There is. In addition, if the threshold value used for detection is set to be loose so as not to be erroneously detected, detection is delayed when clogging occurs. If detection is delayed, energy is wasted.

  The method (3) is a method of indirectly detecting a pressure change in the water circuit by a change in the output of the pump. For this reason, the method (3) may erroneously detect that clogging has occurred, as in the method (2). In addition, if the threshold value used for detection is set to be loose so as not to be erroneously detected, detection is delayed when clogging occurs.

  In the method (4), it is necessary to measure the flow rate of water in order to measure the heating capacity, and a flow rate measuring device such as a flow switch or a flow sensor is required as in the method (1). Therefore, employing the method (4) leads to an increase in the cost of the hot water device. In general, the heating capacity is controlled to be lowered, for example, when the temperature of water in the tank approaches the boiling target temperature. Therefore, even if no clogging occurs, there is a possibility that it is erroneously detected that clogging has occurred if the heating capacity is reduced by control.

  It is also possible to apply the methods (1) to (4) to detection of clogging in each of the primary water circuit and the secondary water circuit in the indirect heating type hot water apparatus. Even in this case, there is the same problem as described above.

  It is an object of the present invention to appropriately detect clogging of a secondary water circuit while suppressing costs in an indirect heating type hot water apparatus.

The hot water apparatus according to the present invention is
A fluid circuit in which the fluid heated by the heat source device circulates;
A water circuit connected to the fluid circuit via a heat exchanger and connected to a tank, wherein the water circuit circulates through the heat exchanger and the tank;
An inflow temperature detection unit for detecting an inflow temperature of water flowing into the tank;
An outflow temperature detection unit for detecting an outflow temperature of water flowing out of the tank;
If the first temperature difference between the inflow temperature detected by the inflow temperature detection unit and the outflow temperature detected by the outflow temperature detection unit is equal to or greater than a predetermined first threshold, it indicates that the water circuit has been clogged. And a notification unit that issues a notification to be displayed.

  In the hot water apparatus according to the present invention, the clogging of the water circuit is detected based on the difference between the inflow and outflow temperatures of the tank. Generally, a temperature sensor for detecting the inflow / outflow temperature of the tank is provided. Therefore, it is not necessary to add a new device in order to detect clogging of the water circuit, and it is possible to suppress additional costs. In addition to cases where clogging occurs, there are few cases where the temperature difference between the inflow and outflow of the tank becomes larger than expected, and the possibility of erroneous detection is low.

1 is a configuration diagram of a hot water device 100 according to Embodiment 1. FIG. The figure which shows the flow of the refrigerant | coolant and water in the hot water apparatus 100 which concerns on Embodiment 1. FIG. FIG. 3 is a configuration diagram of a control device according to the first embodiment. 4 is a flowchart of processing for detecting clogging of the secondary water circuit according to the first embodiment. FIG. 6 is a configuration diagram of a control device according to a second embodiment. 10 is a flowchart of processing for detecting clogging of the secondary water circuit according to the second embodiment.

Embodiment 1 FIG.
FIG. 1 is a configuration diagram of a hot water device 100 according to the first embodiment.
The hot water device 100 includes a heat pump device 10 (an example of a heat source device), a water heater 20, and a heating device 50.

The heat pump device 10 includes a compressor 11, an expansion valve 12, and a heat exchanger 13.
The water heater 20 includes a heat exchanger 21, a heater 22, a heat exchanger 23, a pump 24, a pump 25, a tank 26, and the like.

The compressor 11, the heat exchanger 21, the expansion valve 12, and the heat exchanger 13 are sequentially connected by piping, and the refrigerant circuit 14 in which the refrigerant circulates is configured.
A heat exchanger 21, a heater 22, a heat exchanger 23, and a pump 24 are sequentially connected by a pipe to form a primary water circuit 27 (an example of a fluid circuit) through which water circulates. In addition, the heat exchanger 23, the pump 25, and the tank 26 are sequentially connected by piping, and a secondary water circuit 28 (an example of a water circuit) in which water circulates is configured.

  The primary water circuit 27 is provided with a three-way valve 29 between the heater 22 and the heat exchanger 23. The primary water circuit 27 is branched from the three-way valve 29, and a heating device 50 is connected in the middle, and a heating circuit 31 that joins a junction 30 between the heat exchanger 23 and the pump 24 is connected. .

  In the primary water circuit 27, a flow sensor 32 that measures the flow rate of water and a strainer 33 that discharges dust flowing through the primary water circuit 27 are provided between the junction 30 and the pump 24. . Further, the primary water circuit 27 includes a pressure relief valve 34 for lowering the pressure of the primary water circuit 27 in a pipe branched from the heater 22, and an air vent valve 35 for releasing air in the primary water circuit 27, An expansion tank 36 for temporarily storing surplus water circulating in the primary water circuit 27 is connected.

  A scale capturing device 37 that captures a scale such as calcium carbonate is connected to the secondary water circuit 28 between the heat exchanger 23 and the pump 25.

  The tank 26 is provided with a heater 38 that heats water stored in the tank 26, a supply port 39 that supplies water to sanitary equipment such as a shower, and a water supply port 40 that supplies water into the tank 26. .

  The hot water device 100 includes a temperature sensor a that detects an inflow temperature of water flowing into the tank 26, a temperature sensor b that detects an outflow temperature of water that has flowed out of the tank 26, and a temperature of water circulating in the primary water circuit ( As a fluid temperature), a temperature sensor c for detecting the temperature of the water flowing into the heat exchanger 23, a temperature sensor d for detecting the tank temperature of the water stored in the tank 26, and a temperature sensor e for detecting the outside air temperature. With.

The water heater 20 is for a user to set a boiling target temperature indicating how many times the water stored in the tank 26 is heated, an indoor target temperature indicating how many times the room temperature is heated by heating, and the like. An input / output device 41 is provided.
The water heater 20 has a heating capacity based on the tank temperature detected by the temperature sensor c, the outside air temperature detected by the temperature sensor d, the boiling target temperature set by the input / output device 41, the indoor target temperature, and the like. A control device 42 for controlling the compressor 11, the pump 24, the heater 22 and the like is provided so as to be appropriate. The control device 42 is configured by a microcomputer, for example.

  FIG. 2 is a diagram illustrating the flow of refrigerant and water in the hot water device 100 according to the first embodiment. In FIG. 2, the solid line arrow indicates the refrigerant flow in the refrigerant circuit 14, the broken line arrow indicates the water flow in the primary water circuit 27 and the heating circuit 31, and the alternate long and short dash line arrow indicates the water flow in the secondary water circuit 28. Show.

  In the refrigerant circuit 14, the refrigerant that has become high temperature and high pressure by the compressor 11 flows into the heat exchanger 21. The refrigerant that has flowed into the heat exchanger 21 is heat-exchanged with water circulating in the primary water circuit 27 and condensed to become a liquid refrigerant. At this time, the water circulating in the primary water circuit 27 is heated. The liquid refrigerant passes through the expansion valve 12 and expands to become a low-temperature / low-pressure gas-liquid two-phase refrigerant. The gas-liquid two-phase refrigerant flows into the heat exchanger 13, exchanges heat with the outside air, and evaporates to become a gas refrigerant. The gas refrigerant is again sucked into the compressor 11 and becomes high temperature and high pressure.

In the primary water circuit 27, the water heated by the heat exchanger 21 flows into the heater 22. In the heater 22, when the heating in the heat exchanger 21 is insufficient, the water is further heated. The water flowing out of the heater 22 flows from the three-way valve 29 to the heat exchanger 23 during the hot water supply operation, and flows from the three-way valve 29 to the heating circuit 31 and flows into the heating device 50 during the heating operation.
The water flowing into the heat exchanger 23 during the hot water supply operation is heat-exchanged with the water circulating in the secondary water circuit 28 and cooled. At this time, the water circulating through the secondary water circuit 28 is heated. On the other hand, the water flowing into the heating device 50 during the heating operation is cooled by exchanging heat with the air in the room where the heating device 50 is installed. At this time, the air in the room where the heating device 50 is installed is heated.
The water cooled by the secondary water circuit 28 or the water cooled by the heating device 50 passes through the junction 30 and passes through the pump 24 and flows into the heat exchanger 21 again.

  Here, the case where only one of the hot water supply operation and the heating operation is performed has been described. However, the hot water supply operation and the heating operation can be performed simultaneously. In this case, the water flowing out of the heater 22 is branched by the three-way valve 29, a part flows into the heat exchanger 23, and the rest flows into the heating circuit 31 and flows into the heating device 50. Then, the water that flows into the heat exchanger 23 and exchanges heat with the water circulating in the secondary water circuit 28 and the water that flows into the heating device 50 and exchanges heat with the air in the room are merged at the junction 30. It merges and flows into the heat exchanger 21 again.

  In the secondary water circuit 28, the water heated by the heat exchanger 23 passes through the pump 25 and flows into the upper part of the tank 26. Further, water stored in the tank 26 flows out from the lower part of the tank 26 and flows into the heat exchanger 23. In addition, when the temperature of the water stored in the tank 26 is low, the water stored in the tank 26 is supplementarily heated by the heater 38 based on the control of the control device 42.

  As described above, in the primary water circuit 27 and the secondary water circuit 28, since water circulates, a scale such as calcium carbonate is deposited. Then, the scale may be clogged with the circuit and the flow path may be narrowed. If the flow path becomes narrow, the flow rate of the circulating water decreases and the heating capacity decreases. In addition, when plate-type heat exchangers are used as the heat exchangers 21 and 23, some of the flow paths in the heat exchangers 21 and 23 are clogged, the heat exchange area is reduced, and heating is performed. The ability will be reduced. Therefore, it is necessary to operate the heat pump device 10 for a longer time in order to heat the water to the boiling target temperature during the hot water supply operation than when no clogging occurs. Similarly, it is necessary to operate the heat pump device 10 for a long time in order to heat the air in the room to the indoor target temperature during the heating operation. As a result, energy consumption increases.

In the configuration shown in FIG. 1, the primary water circuit 27 is provided with a flow sensor 32. Therefore, it is possible to detect clogging by the method of measuring the flow rate change of water in Patent Document 1.
On the other hand, the secondary water circuit 28 is not provided with a flow sensor. If a flow sensor is also provided in the secondary water circuit 28, it becomes possible to detect clogging. However, providing a flow sensor in the secondary water circuit 28 leads to an increase in cost. It is also conceivable to detect clogging by applying a method of measuring the output change of the pump 25 as described in Patent Document 1 without providing a flow sensor or the like. However, there is a risk of erroneous detection that clogging has occurred when no clogging has occurred, or there is a risk that detection will be delayed when clogging has occurred.

Here, the secondary water circuit 28 is provided with a scale capturing device 37. Since the scale is captured immediately after the scale is deposited by the scale capturing device 37, the scale is prevented from growing greatly, and the secondary water circuit 28 is not easily clogged. However, as time elapses, many scales adhere to the scale capturing device 37, and the flow path may be clogged at the scale capturing device 37 portion.
Further, when a plate-type heat exchanger is used as the heat exchanger 23, the flow path in the plate-type heat exchanger is very narrow, so even if the scale capturing device 37 is provided, the plate-type heat exchanger There is a risk of clogging the internal flow path.

In the hot water device 100 according to the first embodiment, the control device 42 detects clogging of the secondary water circuit 28 using the water inflow / outlet temperature difference of the tank 26.
When clogging occurs in the secondary water circuit 28, the flow rate of water circulating through the secondary water circuit 28 decreases. On the other hand, the flow rate of the water circulating through the primary water circuit 27 does not change. Therefore, the inflow temperature flowing out from the heat exchanger 23 and flowing into the upper portion of the tank 26 becomes higher than when no clogging occurs.
On the other hand, even if the inflow temperature is high, the flow rate of water circulating through the secondary water circuit 28 is small, so that the tank temperature of the water stored in the tank 26 does not increase immediately. Therefore, the outflow temperature flowing out from the lower part of the tank 26 is lower than the inflow temperature.
Therefore, the control device 42 detects that clogging has occurred due to an increase in the temperature difference between the inflow temperature and the outflow temperature.

FIG. 3 is a configuration diagram of the control device 42 according to the first embodiment. The control device 42 also has a function of controlling the compressor 11 and the like as described above, but FIG. 3 shows only a configuration for detecting clogging of the secondary water circuit 28 for simplicity.
The control device 42 includes an inflow temperature detection unit 421, an outflow temperature detection unit 422, a determination unit 423, and a notification unit 424.

FIG. 4 is a flowchart of processing for detecting clogging of the secondary water circuit 28 according to the first embodiment.
(S11: Temperature detection step)
The inflow temperature detector 421 detects the inflow temperature of the water flowing into the tank 26 by the temperature sensor a. Moreover, the outflow temperature detection part 422 detects the outflow temperature of the water which flowed out of the tank 26 by the temperature sensor b.

(S12: Determination step)
The determination unit 423 determines whether or not the temperature difference (first temperature difference) between the inflow temperature and the outflow temperature detected in S11 is equal to or greater than a predetermined first threshold value.
If the determination unit 423 determines that the first temperature difference is greater than or equal to the first threshold (YES in S12), the process proceeds to S13, and determines that the first temperature difference is less than the first threshold (in S12). NO), the process is terminated.

(S13: Notification process)
The notification unit 424 notifies the user that the secondary water circuit 28 is clogged.
For example, the notification unit 424 notifies the display unit of the input / output device 41 by displaying an error code or the like indicating that clogging has occurred. Of course, the present invention is not limited to this, and the notification unit 424 may notify that clogging has occurred by turning on a predetermined lamp provided in the hot water device 100, or may be notified from a speaker provided in the hot water device 100. It may be notified that clogging has occurred by making a sound. In addition, the notification unit 424 notifies that a clogging has occurred by transmitting an error code or the like to a user's PC (Personal Computer) or a mobile terminal via a network such as a wireless LAN (Local Area Network). May be.

  When the user is notified that clogging has occurred, the clogging of the secondary water circuit 28 can be eliminated by replacing the scale capturing device 37 and the heat exchanger 23 or the like. By eliminating the clogging, it is possible to eliminate the wasteful consumption of energy.

The first threshold value used in S12 is set in the memory or the like of the control device 42 before the start of the processing shown in FIG.
The first threshold value varies depending on various factors such as the performance of the heat pump device 10, the performance of the heat exchangers 21 and 23, and the size of the tank 26. In addition, depending on the setting of the first threshold, the degree of occurrence of erroneous detection, how much clogging can be detected, and the like change. Therefore, for example, the first threshold value is set based on the result of a test that actually causes the secondary water circuit 28 to be clogged.

  As described above, the hot water device 100 according to the first embodiment detects the clogging of the secondary water circuit 28 based on the water inflow / outflow temperature difference of the tank 26. Generally, a temperature sensor for detecting the inflow / outflow temperature of the tank is provided. Therefore, it is not necessary to add a new device in order to detect clogging of the water circuit, and it is possible to suppress additional costs. In addition to cases where clogging occurs, there are few cases where the temperature difference between the inflow and outflow of the tank becomes larger than expected, and the possibility of erroneous detection is low.

  In the above description, the primary water circuit 27 is a circuit through which water circulates. However, the primary water circuit 27 may be a circuit in which a fluid such as brine is circulated instead of water.

  In the above description, the heat pump device 10 is used as a heat source device. However, instead of the heat pump device 10, a boiler or the like may be used as the heat source device.

Embodiment 2. FIG.
In the second embodiment, based on two indices, (1) the difference between the inflow and outflow temperatures of the water in the tank 26 and (2) the temperature difference between the temperature of the water circulating in the primary water circuit 27 and the tank temperature, 2 The detection of clogging of the secondary water circuit 28 will be described.
In the second embodiment, description of the same parts as those of the first embodiment will be omitted, and different parts from the first embodiment will be described.

As described in the first embodiment, except for the case where clogging occurs, the water inflow / outflow temperature difference in the tank 26 is rarely larger than expected, and the secondary difference is based on the water inflow / outlet temperature difference in the tank 26. If the clogging of the water circuit 28 is detected, the possibility of erroneous detection is low.
However, when an abnormality occurs in the temperature sensors a and b, the temperature difference between the inflow and the outflow of the water in the tank 26 becomes larger than expected, and the primary water circuit 27 is not clogged. There is a possibility that the temperature of the water circulating in the water reaches the first threshold value.
Therefore, in the hot water device 100 according to the second embodiment, the control device 42 adds the temperature of the water circulating in the primary water circuit 27 and the tank temperature in addition to the difference in the water inflow / outflow temperature of the tank 26. It is detected that clogging has occurred due to a large temperature difference. As a result, it is possible to prevent erroneous detection that the clogging has occurred that the temperature difference between the water in and out of the tank 26 has become large due to abnormality of the temperature sensors a and b.

FIG. 5 is a configuration diagram of the control device 42 according to the second embodiment. FIG. 5 shows only the configuration for detecting clogging of the secondary water circuit 28 as in FIG.
The control device 42 according to the second embodiment includes a fluid temperature in addition to the inflow temperature detection unit 421, the outflow temperature detection unit 422, the determination unit 423, and the notification unit 424 included in the control device 42 according to the first embodiment illustrated in FIG. A detection unit 425 and a tank temperature detection unit 426 are provided.

FIG. 6 is a flowchart of a process for detecting clogging of the secondary water circuit 28 according to the second embodiment.
(S21: Temperature detection step)
The inflow temperature detector 421 detects the inflow temperature of the water flowing into the tank 26 by the temperature sensor a. Moreover, the outflow temperature detection part 422 detects the outflow temperature of the water which flowed out of the tank 26 by the temperature sensor b.
The fluid temperature detector 425 detects the temperature of the water circulating in the primary water circuit 27 by the temperature sensor c. Moreover, the tank temperature detection part 426 detects the tank temperature of the water stored in the tank by the temperature sensor d.

(S22: Determination step)
The determination unit 423 determines that the temperature difference (first temperature difference) between the inflow temperature and the outflow temperature detected in S21 is equal to or greater than a predetermined first threshold value and the primary water circuit 27 detected in S21. It is determined whether or not the temperature difference (second temperature difference) between the circulating water temperature and the tank temperature is equal to or greater than a predetermined second threshold value.
If the determination unit 423 determines that the first temperature difference is greater than or equal to the first threshold and the second temperature difference is greater than or equal to the second threshold (YES in S22), the process proceeds to S23, and other cases ( NO at S22) and the process ends.

(S23: Notification process)
The notification unit 424 notifies the user that the secondary water circuit 28 is clogged.

The second threshold value used in S22 is set in the memory or the like of the control device 42 before the start of the processing shown in FIG.
Similar to the first threshold value, the second threshold value varies depending on various factors such as the performance of the heat pump device 10 and the performance of the heat exchangers 21 and 23. Therefore, for example, the second threshold value is set together with the first threshold value based on a result of a test that actually causes the secondary water circuit 28 to be clogged.

  As described above, the hot water device 100 according to Embodiment 2 has two indicators, namely, the temperature difference between the inflow and outflow temperatures of the water in the tank 26 and the temperature difference between the temperature of the water circulating in the primary water circuit 27 and the tank temperature. Based on the above, the clogging of the secondary water circuit 28 is detected. Therefore, erroneous detection can be prevented even if the water inflow / outlet temperature difference of the tank 26 becomes large due to some abnormality or the like.

  DESCRIPTION OF SYMBOLS 10 Heat pump apparatus, 11 Compressor, 12 Expansion valve, 13 Heat exchanger, 20 Water heater, 21 Heat exchanger, 22 Heater, 23 Heat exchanger, 24 Pump, 25 Pump, 26 Tank, 27 Primary water circuit, 28 Secondary water circuit, 29 Three-way valve, 30 Junction point, 31 Heating circuit, 32 Flow sensor, 33 Strainer, 34 Pressure relief valve, 35 Air vent valve, 36 Expansion tank, 37 Scale capture device, 38 Heater, 39 Supply port, 40 Water supply port, 41 Input / output device, 42 Control device, 421 Inflow temperature detection unit, 422 Outflow temperature detection unit, 423 determination unit, 424 notification unit, 425 Fluid temperature detection unit, 426 Tank temperature detection unit, 50 Heating device, a, b, c, d, e Temperature sensor.

Claims (2)

A fluid circuit in which the fluid heated by the heat source device circulates;
A water circuit connected to the fluid circuit via a heat exchanger and connected to a tank, wherein the water circuit circulates through the heat exchanger and the tank;
An inflow temperature detection unit for detecting an inflow temperature of water flowing into the tank;
An outflow temperature detection unit for detecting an outflow temperature of water flowing out of the tank;
A fluid temperature detector that circulates through the fluid circuit and detects the fluid temperature of the fluid flowing into the heat exchanger;
A tank temperature detection unit for detecting a tank temperature of water stored in the tank;
Ri der first threshold value or more first temperature difference predetermined for the outflow temperature, wherein the outlet temperature detection unit and the inlet temperature of the inlet temperature detecting unit has detected is detected and the fluid temperature detecting unit detects If the second temperature difference between the fluid temperature and the tank tank temperature at which the temperature detecting section detects the Ru der second threshold value or more predetermined notification unit which issues a notification indicating that the clogging has occurred in the water circuit A hot water apparatus comprising: A fluid circuit in which the fluid heated by the heat source device circulates;
An abnormality notification method in a water heater connected to the fluid circuit via a heat exchanger and connected to a tank, the water circuit comprising a water circuit in which water circulates through the heat exchanger and the tank And
An inflow temperature detection step of detecting an inflow temperature of water flowing into the tank;
An outflow temperature detecting step for detecting an outflow temperature of water flowing out of the tank;
A fluid temperature detection step of circulating the fluid circuit and detecting the fluid temperature of the fluid flowing into the heat exchanger;
A tank temperature detecting step for detecting a tank temperature of water stored in the tank;
Ri der first threshold value or more first temperature difference predetermined outflow temperature detected by the inlet temperature and detected by the inlet temperature detecting step the outlet temperature detection step, and detected by the fluid temperature detecting step If the second temperature difference between the tank temperature detected by the fluid temperature and the tank temperature detecting step Ru der second threshold value or more predetermined notification step of issuing a notification indicating that clogging of the water circuit has occurred An abnormality notification method in a hot water apparatus, comprising:

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