JP7002382B2 - Hot water supply system - Google Patents

Description

The technique disclosed herein relates to a hot water supply system.

Patent Document 1 discloses a hot water supply system. The hot water supply system of Patent Document 1 includes a heat pump that heats water, a hot water storage tank that stores water heated by the heat pump, a hot water outlet that discharges the water stored in the hot water storage tank, and a hot water outlet from the hot water storage tank. It is equipped with a first temperature sensor that detects the temperature of the water. Further, this hot water supply system includes a water supply channel connected to the downstream end of the hot water supply channel and a hot water supply channel connected to the connection portion between the hot water supply channel and the water supply channel. The hot water supply channel supplies water, which is a mixture of water supplied from the hot water supply channel and water supplied from the water supply channel, to the hot water supply location. In addition, this hot water supply system is supplied to the hot water supply point through a mixing valve that adjusts the ratio of the flow rate of water supplied from the hot water supply channel to the hot water supply channel and the flow rate of water supplied from the water supply channel to the hot water supply channel, and a hot water supply channel. A flow sensor (hot water volume sensor and water volume sensor) that detects the flow rate of water, an auxiliary heat source machine that heats the water flowing through the hot water supply channel, and a second temperature that detects the temperature of the water after being heated by the auxiliary heat source machine. It is equipped with a sensor. In addition, this hot water supply system is connected to the hot water supply path on the upstream side of the auxiliary heat source machine and the hot water supply path on the downstream side of the auxiliary heat source machine, and the water flowing through the hot water supply path on the upstream side of the auxiliary heat source machine is supplied from the auxiliary heat source machine. It is equipped with a bypass path for supplying to the hot water supply path on the downstream side, a bypass valve for opening and closing the bypass path, a third temperature sensor for detecting the temperature of water flowing in the hot water supply path on the downstream side of the bypass valve, and a control unit. .. The hot water supply system of Patent Document 1 executes a hot water supply operation in which water stored in a hot water storage tank is supplied to a hot water supply location through a hot water outlet and a hot water supply channel, and an auxiliary heating operation in which water flowing through the hot water supply channel is heated by an auxiliary heat source machine. It is configured to be possible. When the control unit of this hot water supply system executes the hot water supply operation, the detection temperature of the first temperature sensor (that is, the temperature of the water discharged from the hot water storage tank to the hot water supply channel) is lower than the predetermined hot water supply set temperature. If so, perform an auxiliary heating operation. That is, when the hot water storage tank runs out of hot water, the control unit executes the auxiliary heating operation. In this auxiliary heating operation, when the detected flow rate of the flow rate sensor (that is, the flow rate of water supplied to the hot water supply location) is equal to or higher than a predetermined reference flow rate, the control unit executes the first water heater operation control. On the other hand, when the detected flow rate of the flow rate sensor is less than the predetermined reference flow rate, the control unit executes the second water heater operation control. In the first water heater operation control, the control unit sets the detection temperature of the second temperature sensor (that is, the temperature of the water after being heated by the auxiliary heat source machine) to a target heating temperature higher than the hot water supply set temperature. Controls the operation of the auxiliary heat source machine. In the second water heater operation control, the control unit controls the operation of the auxiliary heat source machine so that the detection temperature of the second temperature sensor becomes the hot water supply set temperature. Further, in the auxiliary heating operation of Patent Document 1, the control unit adjusts the temperature of the water supplied to the hot water supply location by adjusting the opening degree of the bypass valve.

Japanese Unexamined Patent Publication No. 2013-224782

In the hot water supply system of Patent Document 1, when the hot water storage tank runs out of hot water, the control unit adjusts the opening degree of the bypass valve. On the other hand, when the flow rate of the water supplied to the hot water supply point is small, the pressure loss of the water flowing through the hot water supply path is small, so that it is conceivable to adopt a configuration in which the control unit completely closes the bypass path. In such a configuration, when the hot water storage tank runs out of hot water, the control unit sends a closing command signal to the bypass valve so that the bypass path is completely closed. The bypass valve operates to completely close the bypass path based on the closure command signal. This prevents water from flowing into the bypass path.

However, an error may occur between the position of the bypass valve after the bypass valve operates based on the closing command signal and the position of the bypass valve when the bypass path is completely closed. That is, even though the bypass valve operates to completely close the bypass path, the bypass path may not be completely closed and a gap may be created. Then, the water flowing through the hot water supply channel upstream of the bypass path flows to the bypass path that is not completely closed and is supplied to the hot water supply point. In such a state, the water that has flowed through the bypass path is mixed with the water that has been heated to the hot water supply set temperature by the auxiliary heat source machine and supplied to the hot water supply location. Therefore, the temperature of the water supplied to the hot water supply location becomes lower than the hot water supply set temperature. If water having a temperature lower than the hot water supply set temperature is supplied to the hot water supply location, the user may feel uncomfortable.

The present specification provides a technique capable of suppressing the supply of water having a temperature lower than the hot water supply set temperature to the hot water supply location.

The hot water supply system disclosed in the present specification is from a heat pump that heats water, a hot water storage tank that stores water heated by the heat pump, a hot water outlet that discharges water stored in the hot water storage tank, and the hot water storage tank. It is connected to a first temperature sensor that detects the temperature of water discharged into the hot water passage, a water supply passage connected to the downstream end of the hot water passage, and a connection portion between the hot water passage and the water supply passage. A hot water supply channel that supplies a mixture of water supplied from the hot water supply channel and water supplied from the hot water supply channel to a hot water supply location, a flow rate of water supplied from the hot water supply channel to the hot water supply channel, and the water supply channel. A mixing valve that adjusts the ratio of the flow rate of water supplied to the hot water supply path, a flow rate sensor that detects the flow rate of water supplied to the hot water supply location through the hot water supply path, and an auxiliary that heats the water flowing through the hot water supply path. A heat source machine, a second temperature sensor that detects the temperature of water after being heated by the auxiliary heat source machine, the hot water supply path upstream of the auxiliary heat source machine, and the hot water supply path downstream of the auxiliary heat source machine. A bypass path that supplies water flowing through the hot water supply path upstream of the auxiliary heat source machine to the hot water supply path downstream of the auxiliary heat source machine, and opens and closes the bypass path based on a command signal. It includes a bypass valve, a third temperature sensor that detects the temperature of water flowing through the hot water supply passage on the downstream side of the bypass valve, and a control unit. The hot water supply system executes a hot water supply operation in which the water stored in the hot water storage tank is supplied to the hot water supply location through the hot water supply passage and the hot water supply passage, and an auxiliary heating operation in which the water flowing through the hot water supply passage is heated by the auxiliary heat source machine. It is configured to be possible. When the control unit executes a hot water supply operation, the detection temperature of the first temperature sensor is lower than the predetermined hot water supply set temperature, and the detection flow rate of the flow rate sensor is lower than the predetermined reference flow rate. Sends a closing command signal to the bypass valve so that the bypass valve completely closes the bypass path, and executes an auxiliary heating operation so that the detection temperature of the second temperature sensor becomes the hot water supply set temperature. After that, when the detection temperature of the third temperature sensor is lower than the detection temperature of the second temperature sensor, the closure command signal is bypassed so that the bypass valve further operates toward the side that closes the bypass path. Further send to the valve.

In the above hot water supply system, if the detected temperature of the first temperature sensor (that is, the temperature of the water discharged from the hot water storage tank to the hot water outlet) is lower than the predetermined hot water supply set temperature, the hot water storage tank is out of hot water. , It is necessary to perform an auxiliary heating operation (that is, to heat the water flowing through the hot water supply channel with the auxiliary heat source machine). If the flow rate detected by the flow rate sensor (that is, the flow rate of water supplied to the hot water supply point) is less than the predetermined reference flow rate, the pressure loss of the water flowing through the hot water supply path is small, so that the bypass path is completely closed. You may. Therefore, in this case, the control unit of the hot water supply system sends a closing command signal to the bypass valve so that the bypass valve completely closes the bypass path, and the detection temperature of the second temperature sensor becomes the hot water supply set temperature. Perform an auxiliary heating operation. This should completely close the bypass path and prevent water from flowing into the bypass path. Also, the entire amount of water flowing through the hot water supply channel should be heated by the auxiliary heat source machine.

However, after that, the temperature detected by the third temperature sensor (that is, the temperature of the water flowing through the hot water supply passage downstream of the bypass valve) becomes the temperature detected by the second temperature sensor (that is, the water after being heated by the auxiliary heat source machine). Temperature) may be less than. In this case, although the control unit has transmitted the closure command signal to the bypass valve, the bypass path is not completely closed and water is flowing through the bypass path. Therefore, in this case, water flows in the bypass path, and the water is mixed with the water after being heated by the auxiliary heat source machine, so that the temperature of the water supplied to the hot water supply point is lowered. Therefore, in this case, the control unit further transmits a closing command signal to the bypass valve so that the bypass valve further operates on the side that closes the bypass path. This completely closes the bypass path and prevents water from flowing into the bypass path. Therefore, the temperature of the water supplied to the hot water supply location does not decrease, and it is possible to suppress the supply of water having a temperature lower than the hot water supply set temperature to the hot water supply location.

The above-mentioned hot water supply system may further include a notification device for notifying an error based on an error signal. After the control unit further transmits a closing command signal to the bypass valve so that the bypass valve further operates to the side that closes the bypass path, the detection temperature of the third temperature sensor is the detection temperature of the second temperature sensor. If the temperature is lower than the detection temperature, an error signal may be transmitted to the notification device.

In the above hot water supply system, the detection temperature of the third temperature sensor is the second temperature sensor after the control unit further sends a closing command signal to the bypass valve so that the bypass valve further operates to the side that closes the hot water supply bypass path. It may be below the detection temperature of. In this case, although the control unit further transmits the closure command signal to the bypass valve in the above case, the bypass path is not completely closed and water is flowing through the bypass path. .. Despite further closure command signals, the bypass path is not completely closed. Therefore, in this case, the control unit transmits an error signal to the notification device. The notifying device notifies the error based on the error signal. According to this configuration, an error can be notified to the user when the bypass path is not completely closed despite the further closing command signal.

It is a figure which shows typically the structure of the hot water supply system which concerns on Example. It is a flowchart which shows the opening and closing process which concerns on Example. It is a flowchart which shows the opening and closing process which concerns on Example. It is a flowchart which shows the opening and closing process which concerns on Example.

The hot water supply system 2 according to the embodiment will be described. As shown in FIG. 1, the hot water supply system 2 according to the embodiment includes a heat pump unit 4, a tank unit 6, and a combustor unit 8. The hot water supply system 2 supplies water at a hot water supply set temperature to a hot water supply location (for example, a faucet in a kitchen). The hot water supply set temperature is a temperature set by the user and is the temperature of water supplied to the hot water supply location. The user sets the hot water supply set temperature desired by the user, for example, by using a remote controller (not shown).

(Structure of heat pump unit 4)
As shown in FIG. 1, the heat pump unit 4 includes a heat pump 40, a tank water circulation path 70, a circulation pump 72, and a heat pump control unit 80.

The heat pump 40 is a heat source that absorbs heat from the outside air and heats the water in the tank water circulation path 70. The heat pump 40 includes a refrigerant circulation path 41 that circulates a refrigerant (alternative freon, for example, R410A, etc.), an evaporator 42 that exchanges heat between the outside air and the refrigerant, a fan 43 that blows outside air to the evaporator 42, and the fan 43. The compressor 44 that compresses the refrigerant to make it high temperature and high pressure, the condenser 45 that exchanges heat between the water in the tank water circulation path 70 and the high temperature and high pressure refrigerant, and the refrigerant after heat exchange is depressurized. It is provided with an expansion valve 46 for lowering the temperature and pressure.

The upstream end of the tank water circulation path 70 is connected to the lower part of the hot water storage tank 100 in the tank unit 6, and the downstream end is connected to the upper part of the hot water storage tank 100. A circulation pump 72 is interposed in the tank water circulation path 70. The circulation pump 72 sends out the water in the tank water circulation path 70 from the upstream side to the downstream side. Further, the tank water circulation path 70 passes through the condenser 45 of the heat pump 40. Therefore, when the heat pump 40 is operated (that is, when the fan 43 and the compressor 44 are operated), the water in the tank water circulation path 70 is heated by the condenser 45 of the heat pump 40. Therefore, when the circulation pump 72 and the heat pump 40 are operated, the water in the lower part of the hot water storage tank 100 is heated by the condenser 45, and the heated water is returned to the upper part of the hot water storage tank 100.

The tank water circulation path 70 is provided with a forward thermistor 74 and a return thermistor 76. The going thermistor 74 is provided in the tank water circulation path 70 on the downstream side of the heat pump 40. The going thermistor 74 detects the temperature of the water heated by the heat pump 40 and sent to the hot water storage tank 100. The return thermistor 76 is provided in the tank water circulation path 70 on the upstream side of the heat pump 40. The return thermistor 76 detects the temperature of the water sent from the hot water storage tank 100 to the heat pump 40.

The heat pump control unit 80 is electrically connected to each element device of the heat pump unit 4 and controls the operation of each element device. Further, the heat pump control unit 80 is provided so as to be able to communicate with each other with the tank control unit 180 of the tank unit 6 and the combustor control unit 280 of the combustor unit 8.

(Structure of tank unit 6)
The tank unit 6 includes a hot water storage tank 100, a tap water supply channel 110, a hot water outlet 130, a hot water supply channel 131, and a tank control unit 180. Further, the tank unit 6 includes a notification device 220.

The hot water storage tank 100 stores hot water heated by the heat pump 40. The hot water storage tank 100 is a closed type, and the outside is covered with a heat insulating material. Water is stored in the hot water storage tank 100 until it is full. In this embodiment, the capacity of the hot water storage tank 100 is 100 L. A hot water storage thermistor 102 (an example of a first temperature sensor) and an intermediate thermistor 104 are attached to the hot water storage tank 100 at predetermined intervals in the height direction of the hot water storage tank 100. Each thermistor 102, 104 detects the temperature of water at its mounting position. For example, the thermistors 102 and 104 detect the temperature of water at positions 6L and 12L from the upper part of the hot water storage tank 100, respectively.

The upstream end of the tap water supply channel 110 is connected to the tap water supply source 112. A water supply thermistor 108 is interposed in the tap water supply path 110. The water supply thermistor 108 detects the temperature of the water flowing in the tap water supply path 110. The downstream side of the tap water supply channel 110 is branched into a first water supply channel 110a and a second water supply channel 110b (an example of a water supply channel). The downstream end of the first water supply channel 110a is connected to the lower part of the hot water storage tank 100. The downstream end of the second water supply channel 110b is connected to the downstream end of the hot water supply channel 130. A water side flow rate sensor 52 is provided in the second water supply channel 110b. The water side flow rate sensor 52 detects the flow rate of water flowing in the second water supply channel 110b.

The upstream end of the hot water outlet 130 is connected to the upper part of the hot water storage tank 100. The second water supply channel 110b of the tap water supply channel 110 is connected to the downstream end of the hot water supply channel 130. The hot water side flow rate sensor 54 is provided in the hot water outlet 130. The hot water side flow rate sensor 54 detects the flow rate of water flowing in the hot water passage 130. A mixing valve 140 is provided at a connection portion between the downstream end of the hot water supply channel 130 and the downstream end of the second water supply channel 110b. The mixing valve 140 mixes the water flowing in the hot water supply channel 130 and the water flowing in the second water supply channel 110b.

The upstream end of the hot water supply passage 131 is connected to the mixing valve 140. The downstream end of the hot water supply channel 131 is connected to the hot water supply point. A combustor 200 (an example of an auxiliary heat source machine) of a combustor unit 8 described later is interposed in the hot water supply passage 131. A mixing thermistor 114 is interposed in the hot water supply passage 131 on the downstream side of the mixing valve 140. The mixing thermistor 114 detects the temperature of the water after being mixed by the mixing valve 140.

A hot water supply bypass path 132 (an example of a bypass path) is connected to the hot water supply path 131. The upstream end of the hot water supply bypass path 132 is connected to the hot water supply path 131 on the upstream side of the combustor unit 8, and the downstream end is connected to the hot water supply path 131 on the downstream side of the combustor unit 8. A bypass valve 141 is provided in the hot water supply bypass path 132. The bypass valve 141 opens and closes the hot water supply bypass path 132. An outlet thermistor 116 (an example of a third temperature sensor) is interposed in the hot water supply passage 131 on the downstream side of the hot water supply bypass passage 132. The outlet thermistor 116 is interposed in the hot water supply passage 131 on the downstream side of the connection portion between the downstream end of the hot water supply bypass passage 132 and the hot water supply passage 131. The outlet thermistor 116 detects the temperature of the water supplied to the hot water supply location by the hot water supply passage 131.

The bypass valve 141 provided in the hot water supply bypass path 132 includes, for example, a stepping motor. The bypass valve 141 operates so as to open and close the hot water supply bypass path 132 by rotating the stepping motor. The bypass valve 141 operates based on the operation command signal received from the tank control unit 180. The operation command signal is, for example, a signal indicating a step angle when the stepping motor rotates. The operation command signal includes, for example, an open command signal and a close command signal. The opening command signal is an operation command signal for the bypass valve 141 to operate on the side that opens the hot water supply bypass path 132. On the other hand, the closure command signal is an operation command signal for the bypass valve 141 to operate on the side that closes the hot water supply bypass path 132.

The tank control unit 180 is electrically connected to each element device of the tank unit 6 and controls the operation of each element device. Further, the tank control unit 180 is provided so as to be able to communicate with each other with the heat pump control unit 80 of the heat pump unit 4 and the combustor control unit 280 of the combustor unit 8.

The notification device 220 is a device that notifies an error by, for example, an image or a voice. The notification device 220 includes, for example, a display for displaying an image and a speaker for outputting sound.

(Combustor unit 8 configuration)
The combustor unit 8 includes a combustor 200 and a combustor control unit 280.

The combustor 200 is an auxiliary heat source machine that heats water passing through the above-mentioned hot water supply passage 131 by the heat of burning fuel (for example, fuel gas). A hot water supply thermistor 210 (an example of a second temperature sensor) is interposed in the hot water supply passage 131 on the downstream side of the combustor 200. The hot water supply thermistor 210 is interposed in the hot water supply passage 131 on the upstream side of the connection portion between the downstream end of the hot water supply bypass passage 132 and the hot water supply passage 131 described above. The hot water supply thermistor 210 detects the temperature of the water supplied to the hot water supply location after being heated by the combustor 200.

A combustor bypass path 133 is connected to the hot water supply path 131 passing through the combustor unit 8. The upstream end of the combustor bypass path 133 is connected to the hot water supply path 131 on the upstream side of the combustor 200, and the downstream end is connected to the hot water supply path 131 on the downstream side of the combustor 200. Further, the hot water supply passage 131 is provided with a water amount servo 142 and a bypass servo 143. The water amount servo 142 adjusts the flow rate of hot water flowing through the hot water supply channel 131. The bypass servo 143 is provided at the connection portion between the upstream end of the combustor bypass path 133 and the hot water supply path 131. The bypass servo 143 adjusts the flow rate of water flowing through the combustor bypass path 133.

Further, a hot water filling passage 134 is connected to the hot water supply passage 131 on the downstream side of the combustor 200. The downstream end of the hot water filling path 134 is connected to the bathtub. The hot water filling path 134 is provided with a hot water filling valve 144. The hot water filling valve 144 adjusts the flow rate of water flowing in the hot water filling path 134.

The combustor control unit 280 is electrically connected to each element device of the combustor unit 8 and controls the operation of each element device. As described above, the combustor control unit 280 can communicate with the heat pump control unit 80 and the tank control unit 180.

Hereinafter, the heat pump control unit 80, the tank control unit 180, and the combustor control unit 280 may be collectively referred to simply as a “control unit”.

Next, the operation of the hot water supply system 2 of this embodiment will be described. The hot water supply system 2 can execute a heat storage operation, a hot water supply operation, and an auxiliary heating operation. Hereinafter, each operation will be described.

(Heat storage operation)
The heat storage operation is an operation in which the water in the hot water storage tank 100 is heated by the heat pump 40. When the control unit instructs the execution of the heat storage operation, the heat pump 40 starts operating (that is, the compressor 44 and the fan 43 are operated), and the circulation pump 72 rotates. When the circulation pump 72 rotates, the water in the hot water storage tank 100 circulates in the tank water circulation path 70. That is, the water existing in the lower part of the hot water storage tank 100 is introduced into the tank water circulation path 70, and when the introduced water passes through the condenser 45 in the heat pump 40, it is heated by the heat of the refrigerant and heated. Is returned to the upper part of the hot water storage tank 100. As a result, high-temperature water is stored in the hot water storage tank 100. A layer of hot water is formed in the upper part of the hot water storage tank 100, and a layer of cold water is formed in the lower part.

(Hot water supply operation)
The hot water supply operation is an operation of supplying the water in the hot water storage tank 100 to the hot water supply location. The hot water supply operation can also be executed during the above heat storage operation. When the hot water tap at the hot water supply location is opened, tap water flows from the tap water supply channel 110 (first water supply channel 110a) to the lower part of the hot water storage tank 100 due to the water pressure from the tap water supply source 112. At the same time, hot water from the upper part of the hot water storage tank 100 is supplied to the hot water supply location via the hot water outlet 130 and the hot water supply channel 131.

When the temperature of the water supplied from the hot water storage tank 100 to the hot water outlet 130 (that is, the detected temperature of the hot water storage thermista 102) is higher than the hot water supply set temperature (for example, 40 ° C.), the control unit opens the mixing valve 140. Tap water is introduced from the second water supply channel 110b to the hot water supply channel 131. Therefore, the water supplied from the hot water storage tank 100 and the tap water supplied from the second water supply channel 110b are mixed by the mixing valve 140. The control unit adjusts the opening degree of the mixing valve 140 so that the temperature of the water supplied to the hot water supply location matches the hot water supply set temperature.

(Auxiliary heating operation)
The auxiliary heating operation is an operation in which the water flowing through the hot water supply passage 131 is heated by the combustor 200. The auxiliary heating operation is performed during the execution of the above-mentioned hot water supply operation. The control unit operates the combustor 200 when the temperature of the water supplied from the hot water storage tank 100 to the hot water outlet 130 is lower than the hot water supply set temperature (for example, 40 ° C.). Therefore, the water passing through the hot water supply channel 131 is heated by the combustor 200. The control unit controls the output of the combustor 200 so that the temperature of the water supplied to the hot water supply location matches the hot water supply set temperature.

Next, the opening / closing process executed by the hot water supply system 2 will be described. This opening / closing process is started when the power of the hot water supply system 2 is turned on. As shown in FIG. 2, in S10 after the opening / closing process is started, the control unit has a total flow rate of the hot water side flow rate and the water side flow rate equal to or higher than a predetermined first reference flow rate (for example, 2.7 L / min). Judge whether or not. The hot water side flow rate is a flow rate detected by the hot water side flow rate sensor 54 provided in the hot water passage 130. The water-side flow rate is a flow rate detected by the water-side flow rate sensor 52 provided in the second water supply channel 110b. The control unit determines whether or not the total flow rate of the detected flow rate of the hot water side flow rate sensor 54 and the detected flow rate of the water side flow rate sensor 52 is equal to or higher than the predetermined first reference flow rate. As a result, the control unit determines whether or not the flow rate of the water supplied to the hot water supply location through the hot water supply path 131 is equal to or higher than the predetermined first reference flow rate. If the total flow rate of the hot water side flow rate and the water side flow rate is equal to or higher than the first reference flow rate, the control unit determines YES in S10 and proceeds to S11. If not, the control unit determines NO in S10 and continues to monitor the total flow rate. If YES in S10, it means that the hot water supply operation has been executed.

In S11, the control unit determines whether or not the detection temperature of the hot water storage thermistor 102 attached to the hot water storage tank 100 is lower than the hot water supply set temperature (for example, 40 ° C.). That is, the control unit determines whether or not the temperature of the water discharged from the hot water storage tank 100 to the hot water outlet 130 is lower than the hot water supply set temperature. If the detected temperature of the hot water storage thermistor 102 is lower than the hot water supply set temperature, the control unit determines YES in S11 and proceeds to S12. If not, the control unit determines NO in S11 and proceeds to S30 (see FIG. 3). If NO in S11, the hot water storage tank 100 is out of hot water.

In S12, the control unit has a second reference flow rate (for example, 15 L / min) in which the total flow rate of the hot water side flow rate (detected flow rate of the hot water side flow rate sensor 54) and the water side flow rate (detected flow rate of the water side flow rate sensor 52) is predetermined. Determine if it is less than. As a result, the control unit determines whether or not the flow rate of water supplied to the hot water supply location through the hot water supply path 131 is less than a predetermined second reference flow rate. If the total flow rate of the hot water side flow rate and the water side flow rate is less than the predetermined second reference flow rate, the control unit determines YES in S12 and proceeds to S13. If not, the control unit determines NO in S12 and proceeds to S40 (see FIG. 4). When YES in S12, the pressure loss of water is small because the flow rate of water flowing through the hot water supply channel 131 is small. On the other hand, when NO in S12, the pressure loss of water is large because the flow rate of water flowing through the hot water supply passage 131 is large.

In S13, the control unit adjusts the opening degree of the mixing valve 140 provided at the connecting portion between the hot water supply channel 130 and the second water supply channel 110b. The control unit adjusts the opening degree of the mixing valve 140 so that the ratio of the hot water side flow rate (detected flow rate of the hot water side flow rate sensor 54) to the water side flow rate (detected flow rate of the water side flow rate sensor 52) is 1: 1. ..

Subsequently, in S14, the control unit transmits an operation command signal to the bypass valve 141 provided in the hot water supply bypass path 132. The control unit transmits a closing command signal to the bypass valve 141 so that the bypass valve 141 operates on the side that closes the hot water supply bypass path 132. The control unit transmits a closing command signal to the bypass valve 141 so that the bypass valve 141 is fully closed and the hot water supply bypass path 132 is completely closed. The bypass valve 141 operates so as to completely close the hot water supply bypass path 132 when it receives the closing command signal. When the bypass valve 141 is fully closed and the hot water supply bypass path 132 is completely closed, water does not flow to the hot water supply bypass path 132. Therefore, the entire amount of water after being mixed by the mixing valve 140 is sent to the combustor unit 8.

Subsequently, in S15, the control unit executes the auxiliary heating operation. When the auxiliary heating operation is executed, the water flowing through the hot water supply passage 131 is heated by the combustor 200 of the combustor unit 8. The control unit controls the output of the combustor 200 so that the temperature of the water after being heated by the combustor 200 matches the hot water supply set temperature. That is, the control unit controls the output of the combustor 200 so that the detected temperature of the hot water supply thermistor 210 matches the hot water supply set temperature.

Subsequently, in S16, the control unit determines whether or not the detected temperature of the outlet thermistor 116 is lower than the detected temperature of the hot water supply thermistor 210. If the detected temperature of the outlet thermistor 116 is lower than the detected temperature of the hot water supply thermistor 210, the control unit determines YES in S16 and proceeds to S17. If not, the control unit determines NO in S16 and returns to S11.

When the bypass valve 141 closes the hot water supply bypass path 132 in S14, water does not flow to the hot water supply bypass path 132 unless the hot water supply bypass path 132 is securely closed and a gap is formed. Therefore, when the water after being heated by the combustor 200 flows through the hot water supply passage 131, the water does not flow from the hot water supply bypass passage 132 into the hot water supply passage 131. Therefore, the temperature of the water flowing through the hot water supply passage 131 on the downstream side of the combustor unit 8 does not decrease. In such a state, the control unit determines NO in S16 above.

On the other hand, if the hot water supply bypass path 132 is not securely closed in S14 and a gap is formed, water will flow to the hot water supply bypass path 132. Then, when the water after being heated by the combustor 200 flows through the hot water supply passage 131, the water flows from the hot water supply bypass passage 132 into the hot water supply passage 131. Therefore, the temperature of the water flowing through the hot water supply passage 131 on the downstream side of the combustor unit 8 decreases. In such a state, the control unit determines YES in S16 above.

Subsequently, in S17, the control unit transmits an operation command signal to the bypass valve 141. In addition to the above S14, the control unit further transmits a closing command signal to the bypass valve 141 so that the bypass valve 141 further operates on the side that closes the hot water supply bypass path 132. The control unit transmits a closing command signal indicating a step angle smaller than the step angle indicated by the closing command signal transmitted in S14 to the bypass valve 141. For example, the control unit transmits a closing command signal indicating a step angle of 1/10 of the step angle in S14 to the bypass valve 141. The control unit transmits a closing command signal to the bypass valve 141 so that the gap of the hot water supply bypass path 132 is completely closed. When the gap of the hot water supply bypass path 132 is completely closed, water does not flow to the hot water supply bypass path 132. Therefore, the entire amount of water after being mixed by the mixing valve 140 is sent to the combustor unit 8.

Subsequently, in S18, the control unit determines whether or not the detected temperature of the outlet thermistor 116 is lower than the detected temperature of the hot water supply thermistor 210. If the detected temperature of the outlet thermistor 116 is lower than the detected temperature of the hot water supply thermistor 210, the control unit determines YES in S18 and proceeds to S19. If not, the control unit determines NO in S18 and returns to S11.

When the bypass valve 141 closes the hot water supply bypass path 132 in S17, water does not flow to the hot water supply bypass path 132 unless the hot water supply bypass path 132 is securely closed and a gap is formed. In such a state, the control unit determines NO in the above S18 as in the above S16.

On the other hand, if the hot water supply bypass path 132 is not securely closed in S17 and a gap is formed, water will flow to the hot water supply bypass path 132. In such a state, similarly to the above S16, the control unit determines YES in the above S18.

Subsequently, in S19, the control unit transmits an error signal to the notification device 220. The notification device 220 notifies an error based on the error signal received from the control unit. The notification device 220 notifies an error by an image or voice such as "the bypass valve is not closed".

Next, a case where the control unit determines NO in the above S11 will be described. As shown in FIG. 3, in S30 after the control unit determines NO in the above S11, the control unit prohibits the auxiliary heating operation. If the auxiliary heating operation is prohibited, the combustor 200 will not operate.

Subsequently, in S31, the control unit adjusts the opening degree of the mixing valve 140. The control unit adjusts the opening degree of the mixing valve 140 so that the temperature of the water after being mixed by the mixing valve 140 matches the hot water supply set temperature. That is, the control unit adjusts the opening degree of the mixing valve 140 so that the detected temperature of the mixing thermistor 114 matches the hot water supply set temperature.

Subsequently, in S32, the control unit transmits an operation command signal to the bypass valve 141. The control unit transmits an opening command signal to the bypass valve 141 so that the bypass valve 141 operates on the side that opens the hot water supply bypass path 132. The control unit transmits an opening command signal to the bypass valve 141 so that the bypass valve 141 is fully opened and the hot water supply bypass path 132 is opened. The bypass valve 141 operates so as to open the hot water supply bypass path 132 when the opening command signal is received. When the bypass valve 141 is fully opened and the hot water supply bypass path 132 is opened, the water mixed by the mixing valve 140 flows into the hot water supply bypass path 132. The water flowing through the hot water supply bypass path 132 is supplied to the hot water supply location. When S32 ends, the control unit returns to S11 above (see FIG. 2).

Next, a case where the control unit determines NO in the above S12 will be described. As shown in FIG. 4, in S40 after the control unit determines NO in the above S12, the control unit adjusts the opening degree of the mixing valve 140. The control unit adjusts the opening degree of the mixing valve 140 so that the ratio of the hot water side flow rate (detected flow rate of the hot water side flow rate sensor 54) to the water side flow rate (detected flow rate of the water side flow rate sensor 52) is 1: 1. ..

Subsequently, in S41, the control unit executes the auxiliary heating operation. When the auxiliary heating operation is executed, the water flowing through the hot water supply passage 131 is heated by the combustor 200 of the combustor unit 8. The control unit controls the output of the combustor 200 so that the temperature of the water after being heated by the combustor 200 becomes a predetermined target temperature (for example, 55 ° C.) higher than the hot water supply set temperature. That is, the control unit controls the output of the combustor 200 so that the detection temperature of the hot water supply thermistor 210 becomes a predetermined target temperature.

Subsequently, in S42, the control unit transmits an operation command signal to the bypass valve 141 to adjust the opening degree of the bypass valve 141. When the opening degree of the bypass valve 141 is adjusted, a part of the water mixed by the mixing valve 140 flows into the hot water supply bypass path 132. The water flowing through the hot water supply bypass path 132 is mixed with the water flowing through the hot water supply channel 131 at the connection portion between the downstream end of the hot water supply bypass path 132 and the hot water supply path 131. That is, the water flowing through the hot water supply bypass path 132 is mixed with the water after being heated by the combustor 200. The control unit adjusts the opening degree of the bypass valve 141 so that the temperature of the water after being mixed at the connection portion between the hot water supply bypass path 132 and the hot water supply path 131 matches the hot water supply set temperature. That is, the control unit adjusts the opening degree of the bypass valve 141 so that the detected temperature of the outlet thermistor 116 matches the hot water supply set temperature. When S42 ends, the control unit returns to S11 above (see FIG. 2).

The configuration and operation of the hot water supply system 2 have been described above. As described above, the hot water supply system 2 includes a heat pump 40 for heating water, a hot water storage tank 100 for storing water heated by the heat pump 40, a hot water outlet 130 for discharging water stored in the hot water storage tank 100, and a hot water storage tank. It is provided with a hot water storage thermistor 102 that detects the temperature of water discharged from 100 to the hot water passage 130. Further, the hot water supply system 2 includes a second water supply channel 110b connected to the downstream end of the hot water supply channel 130, and a hot water supply channel 131 connected to a connection portion between the hot water supply channel 130 and the second water supply channel 110b. .. The hot water supply channel 131 supplies water, which is a mixture of water supplied from the hot water supply channel 130 and water supplied from the second water supply channel 110b, to the hot water supply location. Further, the hot water supply system 2 includes a mixing valve 140 that adjusts the ratio of the flow rate of water supplied from the hot water supply channel 130 to the hot water supply channel 131 and the flow rate of water supplied from the second water supply channel 110b to the hot water supply channel 131, and hot water. It includes a hot water side flow rate sensor 54 for detecting the side flow rate and a water side flow rate sensor 52 for detecting the water side flow rate. The hot water side flow rate sensor 54 and the water side flow rate sensor 52 are examples of flow rate sensors that detect the flow rate of water supplied to the hot water supply location. Further, the hot water supply system 2 includes a combustor 200 that heats the water flowing through the hot water supply passage 131, and a hot water supply thermistor 210 that detects the temperature of the water after being heated by the combustor 200. Further, the hot water supply system 2 is connected to the hot water supply passage 131 on the upstream side of the combustor 200 and the hot water supply passage 131 on the downstream side of the combustor 200, and burns the water flowing through the hot water supply passage 131 on the upstream side of the combustor 200. The temperature of the hot water supply bypass path 132 supplied to the hot water supply path 131 downstream of the machine 200, the bypass valve 141 that opens and closes the hot water supply bypass path 132 based on the command signal, and the water flowing through the hot water supply path 131 downstream of the bypass valve 141. It is equipped with an outlet thermista 116 for detecting. The hot water supply system 2 performs a hot water supply operation in which the water stored in the hot water storage tank 100 is supplied to the hot water supply location through the hot water supply passage 130 and the hot water supply passage 131, and an auxiliary heating operation in which the water flowing through the hot water supply passage 131 is heated by the combustor 200. It is configured to be viable.

The control unit of the hot water supply system 2 is a case where the hot water supply operation is executed, the detection temperature of the hot water storage thermistor 102 is less than a predetermined hot water supply set temperature (for example, 40 ° C.) (YES in S11), and the hot water side flow sensor. When the total flow rate of the detected flow rate of 54 and the detected flow rate of the water side flow sensor 52 is less than the predetermined reference flow rate (YES in S12), a closing command signal such that the bypass valve 141 completely closes the hot water supply bypass path 132. Is transmitted to the bypass valve 141 (S14), and an auxiliary heating operation is executed so that the detected temperature of the hot water supply thermistor 210 becomes the hot water supply set temperature (S15). After that, if the detected temperature of the outlet thermistor 116 is lower than the detected temperature of the hot water supply thermistor 210 (YES in S16), the control unit of the hot water supply system 2 further operates to the side where the bypass valve 141 closes the hot water supply bypass path 132. A closing command signal is further transmitted to the bypass valve 141 (S17).

In the above hot water supply system 2, when the detected temperature of the hot water storage thermistor 102 (that is, the temperature of the water discharged from the hot water storage tank 100 to the hot water outlet 130) is lower than the hot water supply set temperature, the hot water storage tank 100 is in a hot water shortage state. .. In this case, it is necessary to carry out an auxiliary heating operation. Further, when the total flow rate of the hot water side flow rate and the water side flow rate (that is, the flow rate of the water supplied to the hot water supply location) is less than the predetermined reference flow rate, the pressure loss of the water flowing through the hot water supply passage 131 is small, so that the hot water supply is performed. The bypass path 132 may be completely closed. Therefore, in this case, the control unit of the hot water supply system 2 transmits a closing command signal to the bypass valve 141 so that the bypass valve 141 completely closes the hot water supply bypass path 132. At the same time, the control unit executes the auxiliary heating operation so that the detected temperature of the hot water supply thermistor 210 becomes the hot water supply set temperature. As a result, the hot water supply bypass path 132 should be completely closed and water should not flow to the hot water supply bypass path 132. Further, the entire amount of water flowing through the hot water supply channel 131 is sent to the combustor unit 8 and heated by the combustor 200 of the combustor unit 8.

After the control unit of the hot water supply system 2 sends a closure command signal to the bypass valve 141, the detection temperature of the outlet thermistor 116 (that is, the temperature of the water flowing through the hot water supply passage 131 downstream of the bypass valve 141) is detected by the hot water supply thermistor 210. It may be below the temperature (ie, the temperature of the water after being heated by the combustor 200). In this case, although the control unit has transmitted the closure command signal to the bypass valve 141, the hot water supply bypass path 132 is not completely closed and water is flowing through the hot water supply bypass path 132. Is. Therefore, the temperature of the water supplied to the hot water supply location is lowered by mixing the water flowing through the hot water supply bypass path 132 with the water after being heated by the combustor 200. Such a situation occurs, for example, due to the variation between the products of the stepping motor constituting the bypass valve 141. Therefore, in this case, the control unit further transmits a closing command signal to the bypass valve 141 so that the bypass valve 141 further operates on the side that closes the hot water supply bypass path 132. As a result, the hot water supply bypass path 132 is completely closed, and water does not flow to the hot water supply bypass path 132. Therefore, the temperature of the water supplied to the hot water supply location does not decrease, and it is possible to suppress the supply of water having a temperature lower than the hot water supply set temperature to the hot water supply location.

Further, the hot water supply system 2 is provided with a notification device 220 for notifying an error based on an error signal. After the control unit of the hot water supply system 2 further transmits a closing command signal to the bypass valve 141 so that the bypass valve 141 further operates to the side that closes the hot water supply bypass path 132 (S17), the detection temperature of the outlet thermistor 116 is the hot water supply. If the temperature is lower than the detection temperature of the thermistor 210 (YES in S18), an error signal is transmitted to the notification device 220 (S19).

If the detected temperature of the outlet thermistor 116 is lower than the detected temperature of the hot water supply thermistor 210 after the control unit of the hot water supply system 2 further transmits the closure command signal to the bypass valve 141, the actual closing command signal is not included. The hot water supply bypass path 132 is not completely closed, and water is flowing through the hot water supply bypass path 132. Therefore, in this case, the control unit transmits an error signal to the notification device 220. The notification device 220 notifies an error based on the error signal. According to this configuration, it is possible to notify the user of an error when the hot water supply bypass path 132 is not completely closed despite the further closing command signal.

Although each embodiment has been described in detail above, these are merely examples and do not limit the scope of claims. The techniques described in the claims include various modifications and modifications of the specific examples exemplified above.

For example, in the above embodiment, the mixing valve 140 is provided at the connection portion between the downstream end of the hot water supply channel 130 and the downstream end of the second water supply channel 110b, but the configuration is not limited to this. The position where the mixing valve 140 is provided can be changed. For example, a mixing valve 140 may be provided at a branch portion between the first water supply channel 110a and the second water supply channel 110b.

The technical elements described herein or in the drawings exhibit their technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the techniques exemplified in the present specification or the drawings can achieve a plurality of purposes at the same time, and achieving one of the purposes itself has technical usefulness.

2: Hot water supply system, 4: Heat pump unit, 6: Tank unit, 8: Combustor unit, 40: Heat pump, 41: Refrigerator circulation path, 42: Evaporator, 43: Fan, 44: Compressor, 45: Condenser, 46: Expansion valve, 52: Water side flow sensor, 54: Hot water side flow sensor, 70: Tank water circulation path, 72: Circulation pump, 74: Outgoing thermista, 76: Return thermista, 80: Heat pump control unit, 100: Hot water storage tank , 102: Hot water storage thermista, 104: Intermediate thermista, 108: Water supply thermista, 110: Tap water supply channel, 110a: First water supply channel, 110b: Second water supply channel, 112: Tap water supply source, 114: Mixing thermista, 116 : Outlet thermista, 130: Hot water supply path, 131: Hot water supply path, 132: Hot water supply bypass path, 133: Combustor bypass path, 134: Hot water filling path, 140: Mixing valve, 141: Bypass valve, 142: Water volume servo, 143: Bypass servo, 144: Hot water filling valve, 180: Tank control unit, 200: Combustor, 210: Hot water supply thermista, 220: Notification device, 280: Combustor control unit

Claims (2)

A heat pump that heats water,
A hot water storage tank that stores water heated by the heat pump,
A deyu channel that discharges the water stored in the hot water storage tank,
A first temperature sensor that detects the temperature of the water discharged from the hot water storage tank to the hot water passage, and
The water supply channel connected to the downstream end of the hot water channel and
A hot water supply channel that is connected to a connection portion between the hot water supply channel and the water supply channel and supplies water that is a mixture of water supplied from the hot water supply channel and water supplied from the water supply channel to the hot water supply location.
A mixing valve that adjusts the ratio of the flow rate of water supplied from the hot water outlet to the hot water supply channel and the flow rate of water supplied from the water supply channel to the hot water supply channel.
A flow rate sensor that detects the flow rate of water supplied to the hot water supply point through the hot water supply path, and
An auxiliary heat source machine that heats the water flowing through the hot water supply channel,
A second temperature sensor that detects the temperature of water after being heated by the auxiliary heat source machine, and
The water that is connected to the hot water supply path upstream of the auxiliary heat source machine and the hot water supply path downstream of the auxiliary heat source machine and flows through the hot water supply path upstream of the auxiliary heat source machine is supplied from the auxiliary heat source machine. A bypass path that supplies the hot water supply channel on the downstream side,
A bypass valve that opens and closes the bypass path based on an operation command signal,
A third temperature sensor that detects the temperature of water flowing through the hot water supply passage on the downstream side of the bypass valve, and
It has a control unit and
It is configured to be able to execute a hot water supply operation in which the water stored in the hot water storage tank is supplied to the hot water supply location through the hot water outlet and the hot water supply channel, and an auxiliary heating operation in which the water flowing through the hot water supply channel is heated by the auxiliary heat source machine. And
When the control unit executes the hot water supply operation, the detection temperature of the first temperature sensor is lower than the predetermined hot water supply set temperature, and the detection flow rate of the flow rate sensor is lower than the predetermined reference flow rate. Sends a closing command signal to the bypass valve so that the bypass valve completely closes the bypass path, and executes an auxiliary heating operation so that the detection temperature of the second temperature sensor becomes the hot water supply set temperature. After that, when the detection temperature of the third temperature sensor is lower than the detection temperature of the second temperature sensor, the closure command signal is bypassed so that the bypass valve further operates toward the side that closes the bypass path. A hot water supply system that sends more to the valve. It is further equipped with a notification device that notifies an error based on an error signal.
After the control unit further transmits a closing command signal to the bypass valve so that the bypass valve further operates to the side that closes the bypass path, the detection temperature of the third temperature sensor is the detection temperature of the second temperature sensor. The hot water supply system according to claim 1, wherein an error signal is transmitted to the notification device when the temperature is lower than the detection temperature.

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