JP2020060359A - Storage water heater - Google Patents

Abstract

To prevent a temperature of hot water to be delivered from becoming unstable when a user performs hot water delivery operation during return of warmed hot water into a hot water storage tank.SOLUTION: A heat pump water heater 1 for supplying hot water warmed by a water refrigerant heat exchanger 15 to a hot water storage tank 2 includes a three-way valve 10D for switching between returning hot water from the water side of the water refrigerant heat exchanger 15 to the hot water storage tank 2 via piping 6d and piping 8d and returning it to the hot water storage tank 2 via piping 6e. A return control section 420B of a hot water storage control section 420 switches the three-way valve 10D so as to securely introduce the hot water from the water refrigerant heat exchanger 15 to a lower part of the hot water storage tank 2 via the piping 6e until a predetermined period elapses after start of hot water supply treatment and introduce the hot water to an intermediate portion in the height direction of the hot water storage tank 2 via the piping 6d after the predetermined period elapses. Thus, this configuration can prevent a temperature of hot water to be delivered from becoming unstable even when a hot water delivery operation is performed.SELECTED DRAWING: Figure 11

Description

  The present invention relates to a hot water storage type hot water supply device that performs hot water supply processing for supplying hot water to a hot water storage tank.

  Conventionally, in this kind of hot water storage type hot water supply apparatus, as described in Patent Document 1, the heat absorbed from the indoor air in the indoor heat exchanger is used to heat the hot water to the hot water storage tank in the water refrigerant heat exchanger. There was a thing to do (hot water supply processing).

  In the above-mentioned prior art, two return pipes are connected to the hot water storage tank. That is, a return pipe (lower flow path) connected to the lower part of the hot water storage tank and a return pipe (upper flow path) connected to a part other than the lower part of the hot water storage tank (for example, upper flow path) are provided. A switching valve (three-way valve) provided at the branch point makes it possible to switch from which return pipe the hot water from the water side of the water-refrigerant heat exchanger (radiator) is returned to the hot water storage tank.

JP, 2009-281628, A

  By the way, as in the prior art, a return pipe connected to a lower portion of the hot water storage tank (hereinafter, appropriately referred to as “first return pipe”) and a return pipe connected to a portion other than the lower portion of the hot water storage tank (hereinafter, appropriately “Second return pipe”), the second return pipe connected to a portion other than the lower portion of the hot water storage tank and a portion other than the lower portion of the hot water storage tank due to piping layout or other reasons. It may be partially shared with a take-out pipe for taking hot and cold water from.

  In this case, while the hot water is returned to the hot water storage tank through the second return pipe by switching the switching valve, for example, in response to an appropriate hot water operation by the user, the hot water storage tank through the take-out pipe. When hot water is taken out from the hot water tank, the water side of the water-refrigerant heat exchanger → the second return pipe → the hot water tank returning to the hot water tank flows through the hot water tank → the take-out tube as described above. Will be affected by the flow of.

  At this time, in particular, in the refrigerant circulation circuit that exchanges heat with the hot water in the water-refrigerant heat exchanger, while the refrigeration cycle is not stable, for example immediately after the start of the hot water supply process, the flow of hot water returning to the hot water storage tank. When is affected by the above, there is a possibility that the flow rate of hot water flowing out from the water-refrigerant heat exchanger (so-called boiling flow rate) becomes unstable. As a result, there is a problem that the temperature of the hot water discharged may become unstable.

  In order to solve the above problems, in claim 1 of the present invention, a water-refrigerant heat exchanger that functions as a condenser that performs heat exchange between a refrigerant and water, and heat exchange between the refrigerant and air, and evaporation Air heat exchanger that functions as a water heater, a compressor that is connected to the water-refrigerant heat exchanger and the air heat exchanger, a hot water storage tank that stores hot water, and a hot water that is connected to the hot water storage tank and that taps hot water A pipe, and a water side of the water-refrigerant heat exchanger and the hot water storage tank are annularly connected by a hot-water pipe to form a hot-water circulation circuit, and the refrigerant side of the water-refrigerant heat exchanger and the compression Machine, the air heat exchanger, to form a refrigerant circulation circuit by connecting with a refrigerant pipe, while communicating the inlet side of the water-refrigerant heat exchanger to the discharge side of the compressor, of the compressor With respect to the inlet side of the air heat exchanger whose outlet side is communicated with the suction side, In the hot water storage type hot water supply device, wherein the hot water supply device communicates the outlet side of the refrigerant heat exchanger, and performs hot water supply to hot water heated by the water refrigerant heat exchanger to the hot water storage tank, wherein the hot water outlet pipe is the hot water storage tank. Is connected to an intermediate portion in the vertical direction of the hot water storage tank, and is provided with a medium-temperature hot water take-out pipe for taking out hot water from the hot water storage tank. The hot water circulation circuit is connected to a lower portion of the hot water storage tank to return hot water into the hot water storage tank. A water return pipe, the hot water storage tank side is connected to the medium temperature water removal pipe, and a medium temperature water return pipe for returning hot water into the hot water storage tank via the medium temperature water removal pipe; the low temperature water return pipe and the medium temperature water return Provided at a branch point with a pipe, hot water from the water side of the water-refrigerant heat exchanger, a switching valve capable of switching to which of the low-temperature water return pipe or the medium-temperature water return pipe is provided, Cage and before The switching valve is switched so as to introduce the hot water into the low-temperature water return pipe until a predetermined period after the start of the hot water supply process elapses, and after the predetermined period elapses after the start of the hot water supply process. Is provided with a return switching control means for switching the hot water into the medium temperature water return pipe.

  Further, in claim 2, further comprising a boiling temperature detecting means for detecting a temperature of hot water flowing from the water side of the water-refrigerant heat exchanger to the hot water pipe, and the predetermined period is after the start of the hot water supply process. The period is longer than the elapsed time until the detected value of the boiling temperature detecting means reaches a predetermined target value.

  In the third aspect, the predetermined period is longer than the elapsed time after the start of the hot water supply process until a stable timing when the refrigeration cycle of the refrigerant flowing through the refrigerant circulation circuit is considered to be stable.

  Further, in claim 4, a compressor control means for controlling the rotation speed of the compressor, a circulation pump for circulating the hot water in the hot water pipe, a detection value of the boiling temperature detection means, and the target value. The pump control means for controlling the rotation speed of the circulation pump in accordance with the deviation of, and the stable timing, the rotation speed of the circulation pump controlled by the pump control means is equal to or more than a predetermined threshold value. It is the timing.

  Further, in claim 5, the air heat exchanger is an indoor heat exchanger that performs heat exchange between the refrigerant and indoor air, and is connected to the compressor in parallel with the water-refrigerant heat exchanger. The heat pump heat exchanger for exchanging heat between the refrigerant and the outside air, and the heat pump heat exchanger for communicating with the inlet side of the heat pump heat exchanger for the discharge side of the compressor and for the inlet side of the indoor heat exchanger. Atmosphere exhaust heat cooling mode communicating the outlet side of the exchanger, and the water refrigerant heat to the inlet side of the indoor heat exchanger while communicating the inlet side of the water refrigerant heat exchanger to the discharge side of the compressor Mode switching means capable of switching between an exhaust heat utilization cooling mode in which the hot water supply process is performed by communicating the outlet side of the exchanger is provided.

  According to claim 1 of this invention, the inlet side of the water-refrigerant heat exchanger is connected to the discharge side of the compressor, and the outlet side of the air heat exchanger is connected to the suction side of the compressor. The outlet side of the water-refrigerant heat exchanger communicates with the inlet side. The high-temperature high-pressure refrigerant gas discharged from the compressor radiates heat in a water-refrigerant heat exchanger (functioning as a condenser), condenses into liquid refrigerant, and is then evaporated in an air heat exchanger (functioning as an evaporator) Heat is absorbed from and returns to the compressor.

  On the other hand, at this time, the water side of the water-refrigerant heat exchanger is annularly connected to the hot water storage tank via a hot water pipe to form a hot water circulation circuit. Therefore, when the refrigeration cycle of the compressor discharge side → water refrigerant heat exchanger → air heat exchanger → compressor suction side path is formed as described above, the air heat exchanger (evaporator) is set as described above. Function), the heat of the high temperature gas discharged from the compressor after absorbing heat from the air can be radiated to the water side in the water-refrigerant heat exchanger (functioning as a condenser). Thus, the heat received by the heat exchange can be used to heat the hot water (hot water supply process) to the hot water storage tank via the hot water pipe.

  Here, according to the first aspect, in order to heat the hot water as described above, the low temperature water return pipe and the medium temperature water return pipe are provided in the hot water circulation circuit. The low temperature water return pipe is connected to a lower portion of the hot water storage tank and is configured to return hot water (low temperature water) into the hot water storage tank, and the medium temperature water return pipe is connected to a middle portion in a height direction of the hot water storage tank. It is configured to return hot water (medium temperature water) inside. A switching valve is provided at a branch point between the low-temperature water return pipe and the medium-temperature water return pipe, and hot water from the water side of the water-refrigerant heat exchanger is introduced into either the low-temperature water return pipe or the medium-temperature water return pipe. It is possible to switch whether to do it.

  At this time, as a peculiar structure of claim 1 of the present invention, a medium-temperature hot water take-out pipe for taking out hot water (medium-temperature hot water) in the hot-water storage tank is connected to an intermediate portion in the vertical direction of the hot-water storage tank. The medium temperature water return pipe is connected (in other words, the pipe for taking out the medium temperature water from the hot water storage tank and the pipe for returning the medium temperature water into the hot water storage tank are partially shared). In this case, when the hot water is returned to the hot water storage tank through the medium hot water return pipe by switching the switching valve, the hot water returns to the hot water storage tank through the medium hot water take-out pipe.

  As a result, while the hot water is returning to the hot water storage tank as described above, the medium temperature water is taken out from the hot water storage tank through the medium temperature water taking-out pipe in response to an appropriate tapping operation by the user. In the hot water circulation circuit, the water / refrigerant heat exchanger → middle-temperature water return pipe → middle-temperature water withdrawal pipe → hot water returning from the hot water storage tank is discharged through the hot water tank → middle-temperature water withdrawal pipe as described above. It will be affected by the flow of hot and cold water. In particular, while the refrigeration cycle (for example, immediately after the start of the hot water supply process) is not stable in the refrigerant circulation circuit in which the flow of hot water in the hot water circulation circuit and the refrigerant that exchanges heat in the water refrigerant heat exchanger circulate. When the flow of hot water returning to the hot water storage tank is affected by the above, there is a possibility that the flow rate of hot water flowing out from the water-refrigerant heat exchanger (so-called boiling flow rate) becomes unstable. As a result, the temperature of the hot water discharged may be unstable.

  Therefore, according to claim 1, a return switching control means for controlling the switching valve is provided. That is, by the control of the return switching control means, the switching valve, after the start of the hot water supply process, until the predetermined period of time elapses, hot water from the water-refrigerant heat exchanger to the low temperature water return pipe without fail. And introduce. Then, after the lapse of the predetermined period, hot water from the water-refrigerant heat exchanger is introduced into the medium-temperature water return pipe. As a result of such control, by appropriately setting the predetermined period, at least until the refrigerating cycle of the refrigerant circulation circuit is stabilized, the flow of hot water and the hot water flowing back from the water-refrigerant heat exchanger to the hot water storage tank and the It is possible to prevent the influence from being caused by the interference with the flow of hot water discharged from the hot water storage tank. As a result, even when the medium temperature water is taken out from the hot water storage tank while the hot water is returning to the hot water storage tank, the boiling flow rate from the water-refrigerant heat exchanger is stabilized and the hot water is discharged. It is possible to stabilize the temperature of hot water.

  Further, according to claim 2, the switching valve is switched at least at a timing after the temperature of the hot water flowing out from the water side of the water-refrigerant heat exchanger reaches the target value (target boiling temperature). Thereby, at least until the refrigeration cycle of the refrigerant circulation circuit becomes stable, the influence of the interference can be reliably prevented.

  According to the third aspect, it is possible to reliably prevent the influence of the interference from occurring at least until the refrigeration cycle of the refrigerant circulation circuit is stabilized.

  Further, according to claim 4, the compressor control means controls the compressor, and the pump control means controls the circulation pump for circulating the hot water. For example, immediately after the start of the hot water supply process, the number of revolutions of the compressor is relatively low, and in order to reduce the deviation between the temperature of the hot water flowing from the water side of the water-refrigerant heat exchanger and the target temperature, the circulation pump The rotation speed is also made relatively small. After that, with the passage of time, the rotation speed of the compressor gradually increases, and the rotation speed of the circulation pump for reducing the deviation gradually increases. Therefore, by appropriately setting the threshold value related to the rotation speed of the circulation pump, it can be considered that the refrigeration cycle is sufficiently stabilized at the timing when the rotation speed of the circulation pump becomes equal to or higher than the threshold value. You can

  According to the fifth aspect, the cooling operation can be performed in two modes (atmosphere exhaust heat cooling mode and exhaust heat utilization cooling mode). In the exhaust heat utilization cooling mode, the refrigeration cycle in the path of the compressor discharge side → the water refrigerant heat exchanger → the indoor heat exchanger → the compressor suction side as described above is realized.

  On the other hand, in the atmospheric exhaust heat cooling mode, the indoor side as the air heat exchanger in which the inlet side of the heat pump heat exchanger is connected to the discharge side of the compressor and the outlet side is connected to the suction side of the compressor. The outlet side of the heat pump heat exchanger communicates with the inlet side of the heat exchanger. In this case, the high-temperature and high-pressure refrigerant gas discharged from the compressor radiates heat to the outside air in the heat pump heat exchanger (functions as a condenser) and condenses into a liquid refrigerant, which is then evaporated in the indoor heat exchanger (functions as an evaporator). By doing so, it is possible to realize a normal cooling operation in which heat is absorbed from the indoor air and returned to the compressor.

Circuit configuration diagram of the entire water heater with cooling and heating function according to an embodiment of the present invention Functional configuration diagram of the outdoor unit controller Functional configuration diagram of heat exchange control unit Functional block diagram of indoor unit controller Functional configuration diagram of hot water storage control unit Functional configuration diagram of heat-up controller Diagram illustrating the operation during normal cooling operation due to heat exhausted from the atmosphere The figure explaining the example of the operation at the time of hot water supply operation using waste heat. The figure explaining another example of the operation at the time of hot water supply using exhaust heat The figure explaining the interference between the flow returning to the hot water storage tank and the flow discharged from the hot water storage tank. Time transition of the hot water discharge state via the pipe 8d, time transition of the operating state of the waste heat utilization hot water supply operation, time transition of the boiling temperature Tb detected by the boiling temperature sensor, and of the three-way valve switched by the control of the return control unit. The figure explaining the time transition of a switching position, the time transition of the circulation flow rate V in the heating circulation circuit by a boiling pump. Flow chart showing the processing procedure executed by the outdoor unit control unit, the hot water storage control unit, the indoor unit control unit, the heat exchange control unit, and the heat pump control unit.

  An embodiment of the present invention will be described below with reference to FIGS.

  FIG. 1 shows the circuit configuration of the entire heat pump water heater 1 with a cooling and heating function (corresponding to a hot water storage type water heater) of this embodiment.

  1, a heat pump water heater 1 of the present embodiment includes a hot water storage unit 100 including a hot water storage tank 2, an outdoor unit 300 as an air conditioner outdoor unit, an indoor unit 200 as an air conditioner indoor unit, and a heat exchange unit. It has 400 and the heat pump unit 500.

  The heat exchange unit 400 has a coolant-side flow passage 15b and a water-side flow passage 15a for circulating the coolant, and is a water-refrigerant heat exchanger for exchanging heat between the high temperature and high pressure coolant and the hot and cold water in the hot water storage tank 2. 15 and a boiling pump 19 (corresponding to a circulation pump). That is, the water-side flow path 15a of the water-refrigerant heat exchanger 15 and the hot water storage tank 2 are annularly connected by the heating forward pipe 5 and the heating return pipe 6 as hot and cold water pipes, and the hot water storage unit 100 and the heat exchange unit are exchanged. A heating circulation circuit 4 as a hot water circulation circuit is formed in the unit 400.

  The heating outflow pipe 5 includes a pipe 5a and a pipe 5b, and the pipe 5b is connected to a lower portion of the hot water storage tank 2.

  The heating return pipe 6 includes a pipe 6a, a pipe 6b, a pipe 6c, a pipe 6d (corresponding to a medium temperature water return pipe), and a pipe 6e (corresponding to a low temperature water return pipe). The pipes 6b and 6c are three-way valves 10C. And is branched and connected from the pipe 6a. The pipe 6b is connected to the upper part of the hot water storage tank 2, and the pipes 6d and 6e are branched and connected from the pipe 6c via a three-way valve 10D (corresponding to a switching valve). The hot water storage tank 2 side of the pipe 6d is connected to a pipe 8d described later. The pipe 6e is connected to a lower portion of the hot water storage tank 2 and a water supply pipe 7 for supplying water to the hot water storage tank 2. A water supply bypass pipe 9 is branched from the water supply pipe 7.

  The boiling pump 19 is provided in the middle of the pipe 5a, and circulates the hot water from the heating upstream pipe 5 to the heating return pipe 6 through the water side flow path 15a, Circulate. The heating outflow pipe 5 is provided with an inflow water temperature sensor 23 that detects an inflow water temperature T1 (inlet temperature of hot water) flowing into the water-side flow path 15a of the water-refrigerant heat exchanger 15. The return pipe 6 is provided with a boiling temperature sensor 24 (corresponding to boiling temperature detecting means) for detecting a boiling temperature Tb flowing out from the water side flow path 15a toward the hot water storage tank 2.

  The hot water storage tank 2 is also connected with a hot water discharge pipe 8 for discharging hot water stored therein. The hot water discharge pipe 8 includes a pipe 8a, a pipe 8b (corresponding to a medium-temperature water take-out pipe), a pipe 8c, and a pipe 8d ( Equivalent to a medium temperature water extraction pipe). The pipe 8a is connected to the upper part of the hot water storage tank 2 and takes out relatively hot water (hereinafter, simply referred to as "high temperature water") near the upper part of the hot water storage tank 2 to take out the mixing valve 10B. Lead to. The pipe 8d is connected to an intermediate portion in the height direction of the hot water storage tank 2 and is located at an intermediate portion in the vertical direction of the hot water storage tank 2 in a medium temperature region that is neither relatively hot nor cold (hereinafter, simply " Take out "medium-temperature water"). The hot water storage tank 2 side of the pipe 8b is connected to the pipe 8d through a branch point B. The anti-hot water storage tank 2 side of the pipe 8b is connected to the mixing valve 10B. That is, the pipes 8a and 8b are connected so as to join the pipe 8c via the mixing valve 10B. The mixing valve 10B mixes the high temperature water from the pipe 8a, the medium temperature water from the pipe 8d and the medium temperature water from the pipe 8d at a desired ratio, and outputs the mixture to the pipe 8c.

  At this time, as described above, the branch point B is connected to the hot water storage tank 2 side of the pipe 6d. As a result, the hot water introduced from the water-side flow path 15a of the water-refrigerant heat exchanger 15 into the pipe 6d via the pipes 6a and 6c enters the hot water storage tank 2 via the pipe 8d. Will be returned. As a result, the three-way valve 10D returns hot water from the water side flow path 15a to the middle portion in the height direction of the hot water storage tank 2 via the pipe 6d and the pipe 8d, or via the pipe 6e. It has a function of switching whether to return to the lower part of the hot water storage tank 2.

  The pipe 8c and the water supply bypass pipe 9 are connected so as to join the hot water outlet pipe 11 via the mixing valve 10A. The hot water supply pipe 11 is provided with a hot water supply temperature sensor 37 that detects the hot water supply temperature after mixing with the mixing valve 10A. The mixing valve 10A mixes the hot water from the pipe 8c with the water from the water supply bypass pipe 9 based on the detection result of the hot water supply temperature sensor 37 to obtain hot water having a hot water supply set temperature.

  In addition, on the side surface of the hot water storage tank 2, a plurality of hot water storage temperature sensors 12 for detecting the temperature of the hot water in the hot water storage tank 2 (hot water storage temperature) and detecting the heating status of the hot water (in other words, hot water storage status) are arranged vertically. It is provided.

  On the other hand, in the water-refrigerant heat exchanger 15, a refrigerant circulation circuit 30 (including a refrigerant pipe 18, a refrigerant pipe 25, and a refrigerant pipe 26 described later) capable of exchanging heat with hot water in the hot water storage tank 2 (details described later) is The heat exchange unit 400, the outdoor unit 300, and the indoor unit 200 are provided.

  That is, in the outdoor unit 300, the compressor 14 that compresses the refrigerant, the four-way valve 31, and the heat pump that selectively functions as a condenser or an evaporator by heat exchange between the refrigerant and the outside air (details will be described later). The outdoor heat exchanger 17 as a heat exchanger is connected by the refrigerant pipe 18. The outdoor heat exchanger 17 is provided with an outdoor fan 67 for passing outside air through the outdoor heat exchanger 17.

  Specifically, the refrigerant pipe 18 includes a pipe portion 18a on the discharge side of the compressor 14, a pipe portion 18c on the suction side of the compressor 14, and the pipe portion via the four-way valve 31 during heating operation. The pipe part 18b connected to 18a is included. The refrigerant pipe 18 includes pipe portions 18d and 18e that connect the compressor 14 side of the outdoor heat exchanger 17 to the pipe portion 18c via the four-way valve 31 during the heating operation, and the outdoor heat exchanger 17 18 f connected to the side opposite to the compressor 14. The pipe portion 18e includes a two-way valve 122, and the pipe portion 18f includes an expansion valve 113 with a fully closing function as a first opening / closing valve.

  The four-way valve 31 is a valve having four ports, and for each of the two ports for the piping parts 18b and 18d (which constitutes the refrigerant main path) of the refrigerant piping 18, the remaining piping parts are provided. Which of the two ports for 18a and 18c is communicated is switched. The two ports for the pipe parts 18a and 18c are connected by a refrigerant sub-path composed of the pipe parts 18a and 18c arranged in a loop, and the compressor 14 is provided on the refrigerant sub-path. ing. For example, when the four-way valve 31 is switched to the heating side, the pipe portion 18a that is the discharge side of the compressor 14 communicates with the pipe portion 18b that is the inlet side of the indoor heat exchanger 27 described below to cool the air conditioner. When switched to the side, the pipe portion 18a is communicated with the pipe portions 18d and 18e on the outdoor heat exchanger 17 side.

  On the other hand, the heat exchange unit 400 is provided with a refrigerant pipe 25 that serves as a flow path for the refrigerant, and the flow path 15b on the refrigerant side of the water-refrigerant heat exchanger 15 is connected to the refrigerant pipe 25. ing.

  Specifically, the refrigerant pipe 25 is a pipe portion 25a connecting the pipe 18d and one side of the water-refrigerant heat exchanger 15 (specifically, the refrigerant-side flow passage 15b), and the water-refrigerant heat exchange. The pipe portion 25b that connects the other side of the container 15 (specifically, the refrigerant side flow passage 15b) that is the opposite side of the pipe portion 25a and the pipe 18f is included. The piping portion 25a includes a two-way valve 121 as a second opening / closing valve capable of opening / closing the four-way valve 31 and the one side of the water-refrigerant heat exchanger 15, and the piping portion 25b has a fully closing function. The expansion valve 111 is provided.

  On the other hand, the indoor unit 200 is provided with a refrigerant pipe 26 serving as a flow path of the refrigerant, and selectively functions as a condenser or an evaporator by heat exchange between the refrigerant and indoor air (details will be described later). An indoor heat exchanger 27 (corresponding to an air heat exchanger) is connected to the refrigerant pipe 26. The indoor heat exchanger 27 is provided with an indoor fan 77 for passing indoor air through the indoor heat exchanger 27.

  Specifically, the refrigerant pipe 26 is provided in communication with the pipe 18b, and the pipe portion 26a connected to the inlet side of the indoor heat exchanger 27 during heating operation and the like, and the indoor heat exchanger 27. And a pipe portion 26b that connects the outlet side to the pipe 18f during the heating operation, etc.

  Further, the heat pump unit 500 has a flow path 115b on the refrigerant side and a flow path 115a on the water side for circulating the refrigerant, and is a water-refrigerant heat capable of exchanging heat between the high temperature and high pressure refrigerant and the hot and cold water in the hot water storage tank 2. It is provided with an exchanger 115 and a boiling pump 119. That is, the pipe 105a branched from the three-way valve 10F provided in the pipe 5a of the heating outflow pipe 5 is connected to one side (lower side in the figure) of the water side flow passage 115a of the water-refrigerant heat exchanger 115. A pipe 106a, which is connected and is branched from the pipe 6a of the heating return pipe 6, is connected to the other side (the upper side in the drawing) of the water-side flow path 115a. A heating circulation circuit 104 as a hot and cold water circulation circuit is formed in the heat pump unit 500 by means of (corresponding to piping). The boiling pump 119 is provided in the middle of the pipe 105a, and circulates the hot water from the heating upstream pipe 5 to the heating return pipe 6 through the water-side flow path 115a, while the hot water in the hot water storage tank 2 is discharged. Can be circulated.

  Further, the heat pump unit 500 is provided with a refrigerant circulation circuit 130 capable of exchanging heat with the hot and cold water in the hot water storage tank 2 in the water and refrigerant heat exchanger 115. That is, in the refrigerant circulation circuit 130, the compressor 114 that compresses the refrigerant and the outdoor heat exchanger 117 (corresponding to an air heat exchanger) that selectively functions as a condenser or an evaporator by heat exchange between the refrigerant and the outside air. ) And the expansion valve 123 are connected by the refrigerant pipe 118. The outdoor heat exchanger 117 is provided with an outdoor fan 167 for passing outside air through the outdoor heat exchanger 117.

  Here, for example, R32 refrigerant is used as a refrigerant in the refrigerant circulation circuits 30 and 130 to form a heat pump cycle. The refrigerant may be HFC refrigerant, HFO refrigerant, carbon dioxide refrigerant. In the refrigerant pipe 18, a discharge temperature sensor 20 that detects a refrigerant discharge temperature Tout discharged from the compressor 14 is provided in the pipe portion 18a, and the pipe portion 18c is sucked into the compressor 14. An intake temperature sensor 32 for detecting the refrigerant intake temperature Tin of the refrigerant is provided. The outdoor heat exchanger 17 is provided with an outside air temperature sensor 22 that detects the outside air temperature Tair. The detection results of these sensors 20, 32, 22 are input to the outdoor unit control unit 410 provided in the outdoor unit 300, and are further appropriately supplied to the hot water storage control unit 420 and the indoor unit 200 provided in the hot water storage unit 100. It is also input to the indoor unit controller 430 provided, the heat exchange controller 440 provided in the heat exchange unit 400, and the heat pump controller 450 provided in the heat pump unit 500 (may be received via the outdoor unit controller 410). However, it may be received directly from the sensors 20, 32, 22).

  Further, in the refrigerant pipe 25 of the heat exchange unit 400, the refrigerant outflow temperature T2 (third detection value) flowing out from the refrigerant side flow path 15b to the expansion valve 111 is detected in the pipe portion 25b. An outflow temperature sensor 21 is provided. The water-refrigerant heat exchanger 15 is provided with a condensing temperature sensor 33 that detects a refrigerant condensing temperature when the refrigerant condenses in the refrigerant side flow path 15b. The detection results of these sensors 21 and 33 are input to the heat exchange control unit 440 provided in the heat exchange unit 400, and further appropriately, the outdoor unit control unit 410, the indoor unit control unit 430, and the hot water storage control unit. It is also input to 420 and the heat pump control unit 450 (may be received via the heat exchange control unit 440 or may be received directly from the sensors 21, 33).

  Further, in the refrigerant pipe 26 of the indoor unit 200, the indoor heat exchanger 27 is provided with an indoor temperature sensor 34 that detects an indoor temperature Tr (corresponding to the actual room temperature) of the air-conditioned space. The detection result of the sensor 34 is input to the indoor unit control unit 430 provided in the indoor unit 200, and further appropriately, the outdoor unit control unit 410, the hot water storage control unit 420, the heat exchange control unit 440, and the heat pump. It is also input to the control unit 450 (may be received via the indoor unit control unit 430 or may be received directly from the sensor 34).

  The hot water storage control unit 420 of the hot water storage unit 100, the heat exchange control unit 440 of the heat exchange unit 400, the outdoor unit control unit 410 of the outdoor unit 300, the indoor unit control unit of the indoor unit 200. 430 and the heat pump control unit 450 of the heat pump unit 500 are communicably connected to each other, and based on the detection result of each sensor, the hot water storage unit 100 and the heat exchange unit 400 cooperate with each other. , The operation of each device / actuator in the outdoor unit 300, the indoor unit 200, and the heat pump unit 500 is controlled.

  At this time, the indoor unit 200 can be operated by an appropriate operation unit 60 such as a remote controller (hereinafter simply referred to as "remote controller 60"). That is, the remote controller 60 is connected to, for example, the indoor unit control section 430 so that information can be transmitted and received, and the user manually operates the remote controller 60 as appropriate to give a driving instruction indicating which operation is to be performed, that is, , Cooling operation of atmospheric exhaust heat (hereinafter appropriately referred to as "normal cooling operation", etc.), cooling operation of hot water using exhaust heat (hereinafter appropriately referred to as "hot water supply operation using exhaust heat", etc.), heating operation of atmospheric heat absorption (hereinafter appropriate) , "Normal heating operation", etc.) and the like. Contents of instructions from these remote controllers 60 are input to the indoor unit control unit 430 provided in the indoor unit 200, and further, the outdoor unit control unit 410, the heat exchange control unit 440, and the hot water storage control unit 420 are appropriately added. Or to the heat pump controller 450 (may be received via the indoor unit controller 430 or may be received directly from the remote controller 60).

  Next, the outdoor unit controller 410 included in the outdoor unit 300 will be described. Although not shown in detail, the outdoor unit control unit 410 includes a storage unit that stores various data and programs and a control unit that performs calculation / control processing. The functional configuration of the outdoor unit controller 410 will be described with reference to FIG.

  As shown in FIG. 2, the outdoor unit controller 410 includes a four-way valve controller 410A, a compressor controller 410B (corresponding to a compressor controller), an expansion valve controller 410C, and an outdoor fan controller 410D. , And a two-way valve control unit 410E.

  To the four-way valve control unit 410A, the operation instruction of which operation is to be performed, which is instructed by the remote controller 60, and the hot water storage temperature detected by the hot water storage temperature sensor 12 are input.

  The four-way valve control unit 410A actually determines the operation mode of the heat pump water heater 1 (the normal cooling operation described above) according to the operation instruction and the heating status (hot water storage status) of the hot water corresponding to the hot water storage temperature. , Hot water supply operation using exhaust heat, hot water supply operation using exhaust heat, normal heating operation, heating operation using exhaust heat, heating cycle defrost assist operation, assist heating operation, cooling cycle defrost assist operation The operation information to be transmitted is the compressor control unit 410B, the expansion valve control unit 410C, the outdoor fan control unit 410D, the two-way valve control unit 410E, the hot water storage control unit 420, the indoor unit control unit 430, the heat exchange control unit 440, The data is output to the heat pump controller 450. In addition, the four-way valve control unit 410A outputs an opening / closing signal corresponding to the determined operation mode to the four-way valve 31 to switch the four-way valve 31 (details of control contents will be described later).

  In the compressor controller 410B, the outside air temperature Tair detected by the outside air temperature sensor 22, the indoor temperature Tr detected by the indoor temperature sensor 34, and the air conditioner set temperature Tcon (set by the remote controller 60). (Corresponding to the target room temperature) is input (in addition to the case of direct input, the above indirect input is also included. The same applies hereinafter). The compressor control unit 410B rotates the compressor 14 based on at least one of the input temperature and setting according to the operation information input from the four-way valve control unit 410A as described above. Control the number. Particularly in the present embodiment, the rotation speed of the compressor 14 is controlled according to the deviation between the indoor temperature Tr and the air conditioner set temperature Tcon. The rotation speed (control value) of the compressor 14 at this time is also output to an expansion valve control unit 440B of the heat exchange control unit 440 (not shown).

  In the expansion valve control unit 410C, the refrigerant discharge temperature Tout detected by the discharge temperature sensor 20, the refrigerant outflow temperature T2 detected by the outflow temperature sensor 21, and the refrigerant temperature detected by the suction temperature sensor 32. The refrigerant suction temperature Tin is input. The expansion valve control unit 410C controls the opening degree of the expansion valve 113 based on at least one of the input temperatures according to the operation information from the four-way valve control unit 410A (detailed control). The contents will be described later).

  The two-way valve control unit 410E controls opening / closing of the two-way valve 122 according to the operation information from the four-way valve control unit 410A (details of control contents will be described later).

  The outdoor air temperature Tair detected by the outdoor air temperature sensor 22 is input to the outdoor fan control unit 410D. The outdoor fan control unit 410D controls the rotation speed of the outdoor fan 67 based on the outdoor air temperature Tair according to the operation information from the four-way valve control unit 410A.

  The operation mode may be determined by the hot water storage control unit 420, the indoor unit control unit 430, the heat exchange control unit 440, or the heat pump control unit 450. In this case, the operation information corresponding to the determined operation mode is input to the outdoor unit control unit 410 from the hot water storage control unit 420, the indoor unit control unit 430, the heat exchange control unit 440, and the heat pump control unit 450. The four-way valve control unit 410A, the compressor control unit 410B, the expansion valve control unit 410C, the outdoor fan control unit 410D, and the two-way valve control unit 410E perform various controls according to the input operation information.

  Next, the heat exchange control unit 440 provided in the heat exchange unit 400 will be described. The heat exchange control unit 440, like the outdoor unit control unit 410, includes a storage unit and a control unit, and the functional configuration thereof will be described with reference to FIG.

  As shown in FIG. 3, the heat exchange control section 440 functionally includes a pump control section 440A (corresponding to pump control means), an expansion valve control section 440B, and a two-way valve control section 440C.

  The operation information from the outdoor unit controller 410 and the boiling temperature Tb detected by the boiling temperature sensor 24 are input to the pump controller 440A. The pump control unit 440A controls the rotation speed of the boiling pump 19 based on the input boiling temperature Tb according to the operation information input from the outdoor unit control unit 410 as described above. Particularly in the present embodiment, the rotation speed of the boiling pump 19 is controlled according to the deviation between the boiling temperature Tb and a predetermined target boiling temperature (corresponding to a target value).

  In the expansion valve control unit 440B, the operation information from the outdoor unit control unit 410, the outdoor air temperature Tair detected by the outdoor air temperature sensor 22, and from the compressor control unit 410B of the outdoor unit control unit 410. The input rotational speed of the compressor 14 (control value; however, the actual rotational speed of the compressor 14 detected by a known method may be input) and the refrigerant detected by the outflow temperature sensor 21. The outflow temperature T2, the refrigerant suction temperature Tin detected by the suction temperature sensor 32, and the refrigerant discharge temperature Tout detected by the discharge temperature sensor 20 are input. The expansion valve control unit 440B controls the opening and closing and the opening degree of the expansion valve 1110 based on at least one of the input temperature and rotation speed according to the operation information from the outdoor unit control unit 410. To do.

  The operation information from the outdoor unit controller 410 is input to the two-way valve controller 440C. The two-way valve control unit 440C controls the opening / closing operation of the two-way valve 121 based on the operation information (detailed control content will be described later).

  Similar to the above, the operation mode may be determined in the heat exchange control unit 440 (for example, the two-way valve control unit 440C), the indoor unit control unit 430, the hot water storage control unit 420, or the heat pump control unit 450. In this case, the pump control unit 440A and the expansion valve control unit according to the operation information corresponding to the operation mode determined by the two-way valve control unit 440C, the indoor unit control unit 430, the hot water storage control unit 420, and the heat pump control unit 450. 440B performs various controls.

  Next, the indoor unit controller 430 provided in the indoor unit 200 will be described. The indoor unit control unit 430, like the outdoor unit control unit 410 and the heat exchange control unit 440, includes a storage unit and a control unit, and the functional configuration thereof will be described with reference to FIG.

  As shown in FIG. 4, the indoor unit controller 430 functionally includes an indoor fan controller 430A. The indoor fan control unit 430A stores the operation information from the outdoor unit control unit 410, the indoor temperature Tr detected by the indoor temperature sensor 34, and the air conditioner set temperature Tcon set by the remote controller 60. Is entered. The indoor fan control unit 430A controls the rotation speed of the indoor fan 77 based on the indoor temperature Tr and the air conditioner set temperature Tcon according to the operation information from the outdoor unit control unit 410.

  As in the above case, the operation mode may be determined in the indoor unit control unit 430, the heat exchange control unit 440, the hot water storage control unit 420, or the heat pump control unit 450. In this case, the indoor fan control unit 430A performs the control in accordance with the operation information corresponding to the operation mode determined by the indoor unit control unit 430, the heat exchange control unit 440, the hot water storage control unit 420, and the heat pump control unit 450. .

  Next, the hot water storage control unit 420 provided in the hot water storage unit 100 will be described. The hot water storage control unit 420 includes a storage unit and a control unit similar to the outdoor unit control unit 410, the heat exchange control unit 440, and the indoor unit control unit 430, and the functional configuration thereof will be described with reference to FIG.

  As shown in FIG. 5, the hot water storage control unit 420 functionally includes a return control unit 420B (corresponding to a return switching control unit) and a temperature control unit 420C.

  The return control unit 420B includes the operation information from the outdoor unit control unit 410, the hot water storage temperature detected by the hot water storage temperature sensor 12, and the boiling temperature Tb detected by the boiling temperature sensor 24. , Is entered. The return control unit 420B controls the three-way valve 10D according to the operation information from the outdoor unit control unit 410, the hot water heating status (hot water storage status) corresponding to the hot water storage temperature, and the boiling temperature Tb. The switching mode, that is, whether to switch to the pipe 6d side or the pipe 6e side is appropriately controlled. Thereby, hot water after heat exchange in the water-refrigerant heat exchanger 15 is returned to the lower part of the hot water storage tank 2 via the pipes 6c and 6e, or the hot water storage tank via the pipes 6c and 6d and the pipe 8d. It is controlled whether it is returned to the middle part of 2 (details will be described later). Although illustration is omitted, appropriate control is also performed for switching the three-way valve 10C.

  The operation information from the outdoor unit control unit 410, the hot water storage temperature detected by the hot water storage temperature sensor 12, and the hot water supply temperature detected by the hot water supply temperature sensor 37 are input to the temperature control unit 420C. . The temperature control unit 420C determines the hot water supply temperature from the hot water supply temperature sensor 37 according to the operation information from the outdoor unit control unit 410 and the heating status (hot water storage status) corresponding to the hot water storage temperature. The opening degrees of the mixing valves 10A and 10B are appropriately controlled so as to reach the hot water supply set temperature.

  Similar to the above, the operation mode may be determined in the hot water storage control unit 420, the heat exchange control unit 440, the indoor unit control unit 430, or the heat pump control unit 450. In this case, the return control unit 420B and the temperature control unit 420C perform the control according to the operation information corresponding to the operation mode determined by the hot water storage control unit 420, the heat exchange control unit 440, and the indoor unit control unit 430.

  Next, the heat pump controller 450 included in the heat pump unit 500 will be described. The heat pump control unit 450 includes a storage unit and a control unit similar to the outdoor unit control unit 410, the heat exchange control unit 440, the indoor unit control unit 430, and the hot water storage control unit 420, and its functional configuration is shown in FIG. Will be described.

  As shown in FIG. 6, the heat pump controller 450 functionally includes a pump controller 450A, a compressor controller 450B, an expansion valve controller 450C, and an outdoor fan controller 450D.

  The pump control unit 450A has the operation information from the outdoor control unit 410 and an outlet from a temperature sensor (not shown) provided on the outlet side of the water-side flow passage 115a of the water-refrigerant heat exchanger 115. The temperature and are entered. The pump control unit 450A controls the rotation speed of the boiling pump 119 based on at least one of the input temperature and setting according to the operation information input as described above.

  The operation information from the outdoor unit controller 410 and the outside air temperature Tair detected by the outside air temperature sensor 22 are input to the compressor controller 450B. The compressor control unit 450B controls the rotation speed of the compressor 114 based on at least one of the input temperature and setting according to the operation information input as described above.

  The expansion valve control unit 450C includes the operation information from the outdoor unit control unit 410 and the refrigerant discharge temperature detected by a discharge temperature sensor 20 (not shown) provided on the discharge side of the compressor 114. Is entered. The expansion valve control unit 450C controls the opening degree of the expansion valve 123 based on at least one of the input temperatures according to the operation information.

  The operation information from the outdoor unit control unit 410 and the outdoor air temperature Tair detected by the outdoor air temperature sensor 22 are input to the outdoor fan control unit 450D. The outdoor fan control unit 450D controls the rotation speed of the outdoor fan 167 based on the outdoor air temperature Tair according to the operation information.

  Note that the operation mode may be determined in the heat pump control unit 450, the hot water storage control unit 420, the indoor unit control unit 430, or the heat exchange control unit 440 as in the above. In this case, the compressor controller 450B and the expansion valve controller are controlled according to the operation information corresponding to the operation mode determined by the heat pump controller 450, the hot water storage controller 420, the indoor unit controller 430, and the heat exchange controller 440. The unit 450C and the outdoor fan control unit 450D perform the control.

  The heat pump control unit 450 is controlled by the compressor control unit 450B, the expansion valve control unit 450C, and the outdoor fan control unit 450D, even when the heat exchange in the water refrigerant heat exchanger 15 is not performed (or In addition to the execution of the heat exchange in the water-refrigerant heat exchanger 15), a boiling operation or the like for heating and supplying hot water in the hot water storage tank 2 can be executed.

  Here, as described above, in the heat pump water heater 1 of the present embodiment, each type of operation such as the normal cooling operation, the exhaust heat utilization hot water supply operation, and the normal heating operation can be selectively executed. Hereinafter, details of each operation will be sequentially described.

<Normal cooling operation>
First, the normal cooling operation will be described with reference to FIG. 7. During the normal cooling operation shown in FIG. 7 (corresponding to the atmosphere exhaust heat cooling mode), the four-way valve control unit 410A causes the four-way valve 31 to connect the pipe portion 18a to the pipe portion 18d and to connect the pipe to the pipe portion 18d. The portion 18c can be switched to a position (the cooling side described above) where the portion 18c communicates with the pipe portion 18b. The two-way valve control units 410E and 440C switch the two-way valve 122 to the open state and the two-way valve 121 to the closed state. Further, the expansion valve control units 410C and 440B control the expansion valve 113 to a state in which it is adjusted to an appropriate opening degree and the expansion valve 111 to a fully closed state.

  As a result, the piping portion 18a on the discharge side of the compressor 14 → the piping portion 18d → the piping portion 18e (two-way valve 122) → the outdoor heat exchanger 17 → the piping portion 18f (expansion valve 113) → the piping portion 26b → the indoor heat exchange A refrigerant path is formed from the container 27 → the piping portion 26a → the piping portion 18b → the suction side piping portion 18c of the compressor 14.

  As a result, after the refrigerant in a gas state sucked at low temperature and low pressure is compressed by the compressor 14 to become high temperature and high pressure gas, the outdoor fan 67 is driven to rotate and the outdoor heat exchanger functions as a condenser. At 17, heat exchange with the outside air is performed and heat is released to change to a high-pressure liquid. The refrigerant that has become a liquid in this way is appropriately decompressed in the expansion valve 113 to become a low temperature / low pressure liquid and easily evaporated, and in the indoor heat exchanger 27 that functions as an evaporator when the indoor fan 77 is driven to rotate. The air to be air-conditioned is cooled by absorbing heat from the room air, evaporating and changing to gas, and returns to the compressor 14 again as low-temperature low-pressure gas.

<Hot water supply operation using waste heat>
Next, a hot water supply operation using exhaust heat will be described with reference to FIGS. 8 and 9. 8 and 9, during the hot water supply using exhaust heat (corresponding to the cooling mode using exhaust heat), the four-way valve control unit 410A causes the four-way valve 31 to perform the cooling operation as in the normal cooling operation. Can be switched to the side. Further, the two-way valve control sections 410E and 440C switch the two-way valve 122 to the closed state and the two-way valve 121 to the open state. Further, the expansion valve control units 410C and 440B control the expansion valve 113 to a fully closed state and the expansion valve 111 to a state in which it is adjusted to an appropriate opening degree.

  As a result, the pipe portion 18a on the discharge side of the compressor 14 → the pipe portion 18d → the pipe portion 25a (two-way valve 121) → the water-refrigerant heat exchanger 15 → the pipe portion 25b (expansion valve 111) → the pipe portion 26b → the indoor heat The refrigerant path of the exchanger 27 → the pipe portion 26a → the pipe portion 18b → the suction side pipe portion 18c of the compressor 14 is formed.

  As a result, after the refrigerant in the gas state sucked in at low temperature and low pressure is compressed by the compressor 14 to become high temperature and high pressure gas, the refrigerant on the refrigerant side of the water refrigerant heat exchanger 15 that functions as a condenser. It changes into a high-pressure liquid while releasing heat in the flow path 15b. The thus-liquefied refrigerant is appropriately decompressed in the expansion valve 111 to become a low-temperature / low-pressure liquid and easily evaporated, and in the indoor heat exchanger 27 that functions as an evaporator when the indoor fan 77 is driven to rotate. The air to be air-conditioned is cooled by absorbing heat from the room air, evaporating and changing to gas, and returns to the compressor 14 again as low-temperature low-pressure gas.

  Further, the boiling pump 19 is rotated under the control of the pump control unit 440A, so that the low-temperature water (unheated water) taken out from the pipe 5b connected to the lower portion of the hot water storage tank 2 becomes the water-refrigerant heat exchanger 15. After being heated by receiving heat from the condensing refrigerant in the water side flow path 15a, the water is returned to the hot water storage tank 2 (hot water supply process). As a result of the above, the cooling exhaust heat in the summer can be utilized for heating the hot water to the hot water storage tank 2 (hot water supply).

  At this time, by switching the three-way valve 10D to the side of the pipe 6e, as shown in FIG. 8, hot water from the water-refrigerant heat exchanger 15 can be returned to the lower portion (bottom portion) of the hot water storage tank 2. By switching the three-way valve 10D to the side of the pipe 6d, hot water after heating from the water-refrigerant heat exchanger 15 can be returned to the intermediate portion in the vertical direction of the hot water storage tank 2 as shown in FIG. . This switching is generally performed, for example, based on the temperature of the hot water from the water-refrigerant heat exchanger 15 (that is, according to the boiling temperature Tb detected by the sensor 24). That is, if the hot water from the water-refrigerant heat exchanger 15 is the medium temperature water, the three-way valve 10D is switched to the pipe 6d side and the hot water (medium temperature water) is returned to the vertical middle portion of the hot water storage tank 2. If the hot and cold water from the water-refrigerant heat exchanger 15 is in a temperature range lower than that of the medium-temperature water (hereinafter, appropriately referred to as "low-temperature water"), the three-way valve 10D is switched to the pipe 6e side and hot water ( The low temperature water) is returned to the lower part (bottom part) of the hot water storage tank 2.

  As described in the operation mode, in the present embodiment, the four-way valve 31, the two-way valves 122 and 121, the expansion valves 113 and 111, and the outdoor unit controller 410 that controls these. The hot water storage control unit 420, the indoor unit control unit 430, and the heat exchange control unit 440 function as the mode switching unit described in each claim.

<Interference between the flow returning to the hot water storage tank and the flow discharged from the hot water storage tank>
By the way, in the present embodiment, as a unique configuration, as described above, the pipe 8d for taking out hot water (the medium temperature water) in the hot water storage tank 2 after heating from the water-refrigerant heat exchanger 15 is used. The pipe 6d for returning hot water is connected. Therefore, as described above, when hot water is returned to the hot water storage tank 2 through the pipe 6d by switching the three-way valve 10D, the hot water returns to the hot water storage tank 2 through the pipe 8d.

  Here, while hot water is returning to the intermediate portion in the hot water storage tank 2 along the route of the pipe 6d → the pipe 8d → the hot water storage tank 2 as described above, as shown in FIG. In some cases, the medium temperature water may be taken out of the hot water storage tank 2 through the pipes 8b and 8d in response to the hot water discharge operation (see the broken line in FIG. 10). In this case, as described above, the water-refrigerant heat exchanger 15 → the pipe 6d → the pipe 8d → the hot water flow returning to the hot water storage tank 2 (see the thick line in FIG. 10) is the hot water storage tank 2 → the pipe 8d → the pipe as described above. 8b-> pipe 8c-> hot water outlet pipe 11-> ...

  In particular, in the refrigerant circulation circuit 30, while the refrigeration cycle is not stable, for example immediately after the start of the hot water supply process, the flow of hot water flowing out of the water refrigerant heat exchanger 15 and returning to the hot water storage tank 2 (see FIG. 10 (see thick line), the flow rate of the hot water (so-called boiling flow rate) may become unstable. As a result, the temperature of the hot water discharged (see the broken line in FIG. 10) may become unstable.

<Control Method of Switching Valve According to Embodiment>
Therefore, in response to the above, in the present embodiment, the return control unit 420B controls the three-way valve 10D, and after the start of the hot water supply process, the water-refrigerant heat exchanger 15 continues until a predetermined period elapses. The hot water from is always introduced into the pipe 6e (in other words, the lower part of the hot water storage tank 2), and is introduced into the pipe 6d (in other words, the middle part of the hot water storage tank 2) after the lapse of the predetermined period. .

  An example of such control contents will be described with reference to FIG. FIG. 11A shows the time transition of the hot water discharge state through the pipe 8d, and FIG. 11B shows the time transition of the operating state of the waste heat utilization hot water supply operation. Further, FIG. 11C shows a time transition of the boiling temperature Tb detected by the boiling temperature sensor 24, and FIG. 11D shows the three-way valve 10D which is switched by the control of the return control unit 420B. The time transition of the switching position of is shown. Then, FIG. 11 (e) shows a time transition of the circulation flow rate V in the heating circulation circuit 4 by the boiling pump 19.

  That is, in FIG. 11, in this example, tapping from the pipe 8d is started based on a user operation before time t0 (see FIG. 11A), and the three-way valve 10D is connected to the pipe 6e. It is in a state of being switched to the side (the lower side of the hot water storage tank 2) (see FIG. 11D).

  In this state, the waste heat utilization hot water supply operation is started at time t0 (see FIG. 11 (b)). At the beginning of this operation, the boiling temperature Tb is equal to the feed water temperature from the feed water pipe 7 (see FIG. 11 (c)). In addition, at the beginning of the operation, the rotation speed of the compressor 14 is relatively low in order to stably start the compressor 14 (by the control of the compressor control unit 410B). As a result, in order to reduce the deviation between the boiling temperature Tb of the hot water from the water side of the water-refrigerant heat exchanger 15 and the target boiling temperature (by the control of the pump control unit 440A), the boiling pump 19 The number of revolutions, in other words, the circulation flow rate V in the heating circulation circuit 4 is also relatively small (see FIG. 11 (e)).

  After that, as the compressor 14 stably rises with time, the rotation speed of the compressor 14 gradually increases, and the boiling temperature Tb gradually increases due to the heat received by the water-refrigerant heat exchanger 15. After reaching the target boiling temperature at time t1 (see FIG. 11 (c)), it becomes substantially constant. Further, in order to reduce the deviation between the boiling temperature Tb of the hot water and the target boiling temperature, the rotation speed of the boiling pump 19 (in other words, the circulation flow rate V) gradually increases, and for example, at time t2. After exceeding a predetermined threshold value Vth in, the value reaches a sufficiently large value V1 which is larger than that and becomes substantially constant (see FIG. 11 (e)).

  The threshold value Vth is set in advance in correspondence with, for example, a state in which the refrigeration cycle of the refrigerant flowing through the refrigerant circulation circuit 30 can be regarded as stable. Further, the time t2 is a time representing a timing at which the refrigeration cycle can be regarded as stable. Alternatively, instead of the threshold value Vth of the circulation flow rate V, the rotation speed N of the boiling pump 19 corresponding to the circulation flow rate V (corresponding to a state in which the refrigerating cycle of the refrigerant can be considered to be stable similarly to the above) Even when the appropriate threshold value Nth provided is used, the behavior of the rotation speed N with respect to the threshold value Nth is the same as that in FIG. 11 (e).

  After the time t2, at a time t3 when a predetermined period (for example, 4 minutes) that has been set in advance has elapsed from the time t0, the three-way valve 10D is switched to the pipe 6d side by the control of the return control unit 420B ( See FIG. 11D). As a result, the hot water from the water-refrigerant heat exchanger 15 is introduced into the intermediate portion of the hot water storage tank 2 via the pipe 6d and the pipe 8d.

  In addition, in FIG. 11, an example in which the exhaust heat utilization hot water supply operation is started after the hot water discharge is started has been described, but the same is true when the exhaust heat utilization hot water supply operation is started before the hot water discharge is started.

<Processing procedure>
FIG. 12 is a flowchart showing a processing procedure executed by the outdoor unit control unit 410, the hot water storage control unit 420, the indoor unit control unit 430, the heat exchange control unit 440, and the heat pump control unit 450 in order to realize the above method. Explained by.

  In FIG. 12, first, in step S10, for example, the outdoor unit control unit 410 determines whether or not the start of the exhaust heat utilization hot water supply operation is instructed by an appropriate operation of the remote controller 60. If the operation start is not instructed, this determination is not satisfied (S110: NO), and the process waits in a loop until this determination is satisfied. If the start is instructed, this determination is satisfied (S10: YES), and the routine goes to Step S20.

  In step S20, the return control unit 420B of the hot water storage control unit 420 outputs a control signal to the three-way valve 10D to switch the three-way valve 10D to the pipe 6e side. Note that if the three-way valve 10D has already been switched to the pipe 6e side before execution of step S20, this step S20 may be omitted. Then, it transfers to step S30.

  In step S30, the outdoor unit control unit 410, the hot water storage control unit 420, the indoor unit control unit 430, and the heat exchange control unit 440 cooperate with each other to start the exhaust heat utilization hot water supply operation. In this case, as shown in FIG. 8, the hot water after heat exchange in the water-refrigerant heat exchanger 15 is returned to the lower portion of the hot water storage tank 2 through the pipes 6c and 6e.

  Then, in step S40, the return controller 420B of the hot water storage controller 420 determines that the boiling temperature Tb detected by the boiling temperature sensor 24 (corresponding to the detected value in the claims) is the target boiling temperature (claim). It corresponds to the target value described in the section (see FIG. 11C) and it is determined whether or not it has reached. If the target boiling temperature has not been reached, this determination is not satisfied (S40: NO), and the process waits in a loop until the determination is satisfied. If the target boiling temperature has been reached, this determination is satisfied (S40: YES), and the routine goes to Step S50.

  Note that, for example, a rotation speed sensor for detecting the rotation speed of the boiling pump 19 is appropriately provided (see a chain double-dashed line in FIG. 4), and a step 35 (not shown) provided separately between the steps S30 and S40. ), Whether or not the detected rotation speed N is equal to or higher than the threshold value Nth (or the circulation flow rate V calculated based on the rotation speed N is equal to or higher than the threshold value Vth). It may be determined. In this case, the process waits in a loop at step S35 until the determination is satisfied, and after the determination is satisfied, the process proceeds from step S35 to step S40.

  In step S50, the return control part 420B of the hot water storage control part 420 determines whether or not 4 minutes (corresponding to the predetermined period in the claims) have elapsed after the start of the exhaust heat utilization hot water supply operation in step S30. To do. Note that 4 minutes is an example of the predetermined period, and a value different from this may be appropriately set. This determination is not satisfied until 4 minutes have elapsed (S50: NO), and the loop waits. When 4 minutes have elapsed, this determination is satisfied (S50: YES), and the routine goes to Step S60.

  In step S60, the return control unit 420B of the hot water storage control unit 420 outputs a control signal to the three-way valve 10D to switch the three-way valve 10D to the pipe 6d side. As a result, as shown in FIG. 9, hot water after heat exchange in the water-refrigerant heat exchanger 15 is returned to the intermediate portion of the hot water storage tank 2 through the pipes 6c, 6d, 8d. Become.

  After that, in step S70, the hot water storage control unit 420 determines whether or not a predetermined boiling end timing, which is predetermined to end the exhaust heat utilization hot water supply operation started in step S30, has arrived. To do. Specifically, for example, it may be determined based on the detection result of the hot water storage temperature sensor 12 whether or not a predetermined amount of heated hot water has been stored in the hot water storage tank 2. If the boiling end timing has not come, this determination is not satisfied (S70: NO), and the process waits in a loop until this determination is satisfied. If the boiling end timing has come, this determination is satisfied (S70: YES), and the routine goes to Step S80.

  In step S80, the outdoor unit control unit 410, the hot water storage control unit 420, the indoor unit control unit 430, and the heat exchange control unit 440 cooperate with each other to end the exhaust heat utilization hot water supply operation. Then, this flow ends.

<Effect of Embodiment>
As described above, in the heat pump water heater 1 according to the present embodiment, the three-way valve 10D is controlled by the return control unit 420B so that the three-way valve 10D starts a predetermined hot water supply operation using the exhaust heat. Hot water from the water-refrigerant heat exchanger 15 is always introduced into the lower portion (bottom portion) of the hot water storage tank 2 through the pipes 6c and 6e until 4 minutes have elapsed). Then, after the lapse of the predetermined period (4 minutes), hot water from the water-refrigerant heat exchanger 15 is introduced into the intermediate portion of the hot water storage tank 2 through the pipes 6c, 6d, 8d. As a result of such control, at least until the refrigeration cycle of the refrigerant circulation circuit 30 is stabilized by the appropriately set predetermined period (4 minutes), the water-refrigerant heat exchanger 15 moves to the hot water storage tank 2. It is possible to prevent the influence (see FIG. 10) caused by the interference between the returning hot water flow and the hot water flow discharged from the hot water storage tank 2. As a result, even when hot water is taken out from the hot water storage tank 2 while hot water is returning to the hot water storage tank 2, the boiling flow rate from the water-refrigerant heat exchanger 15 is stabilized. It is possible to stabilize the temperature of hot water discharged.

  Further, particularly in the present embodiment, during the predetermined period (4 minutes in the above example), the boiling temperature Tb detected by the boiling temperature sensor 24 is the target boiling temperature after the start of the exhaust heat utilization hot water supply operation. Is a period longer than the elapsed time until reaching (the time from time t0 to time t1 in the example of FIG. 11). In this way, by switching the three-way valve 10D at a later timing at least after the boiling temperature Tb of the hot and cold water from the water-side flow path 15a of the water-refrigerant heat exchanger 15 reaches the target boiling temperature, At least until the refrigeration cycle of the refrigerant circulation circuit 30 stabilizes (the time from time t0 to time t2 in the example of FIG. 11), the influence of the interference can be reliably prevented.

  Further, particularly in the present embodiment, the cooling operation can be performed in two modes (normal cooling operation and waste heat utilization hot water supply operation). In the hot water supply operation using the exhaust heat, the refrigeration cycle is realized in the path of the discharge side of the compressor 14 → the heat exchanger 15 of the water refrigerant → the indoor heat exchanger 27 → the suction side of the compressor 14 as described above. On the other hand, in the normal cooling operation, the high-temperature and high-pressure refrigerant gas discharged from the compressor 14 radiates heat to the outside air in the outdoor heat exchanger 17 to be condensed and becomes a liquid refrigerant, and then is evaporated in the indoor heat exchanger 27 to cause indoors. A normal cooling operation in which heat is absorbed from the air and returned to the compressor 14 can be realized.

  Further, particularly in the present embodiment, during the predetermined period (4 minutes in the above example), after the start of the exhaust heat utilization hot water supply operation, a stable timing when the refrigeration cycle of the refrigerant flowing through the refrigerant circulation circuit 30 can be regarded as stable ( In the example of FIG. 11, the time is longer than the elapsed time up to time t2 (the time from time t0 to time t2 in the example of FIG. 11). Thereby, at least until the refrigeration cycle of the refrigerant circulation circuit 30 stabilizes, it is possible to reliably prevent the influence of the interference.

  Further, particularly in the present embodiment, the compressor control unit 410B of the outdoor unit control unit 410 controls the compressor 14, and the pump control unit 440A of the heat exchange control unit 440 controls the boiling pump 19 that circulates hot water. Then, by appropriately setting the threshold value Nth relating to the rotation speed N of the boiling pump 19 as described above, refrigeration is performed at the timing when the rotation speed N of the boiling pump 19 becomes equal to or more than the threshold value Nth. It can be considered that the cycle is fully stabilized.

  The present invention is not limited to the above embodiments, but is applicable without departing from the spirit of the present invention. For example, in the above, in the case where the endothermic heat in the indoor heat exchanger 27 of the refrigerant circulation circuit 30 is received by the water / refrigerant heat exchanger 15 to heat the hot and cold water into the hot water storage tank 2 (the exhaust gas shown in FIGS. 8 and 9). In the heat-utilizing hot water supply operation), the example in which the method of the present invention is applied has been described, but the present invention is not limited to this. That is, in the case where the heat absorption in the outdoor heat exchanger 117 of the refrigerant circulation circuit 130 is received by the water-refrigerant heat exchanger 115 to heat the hot water into the hot water storage tank 2 via the heating circulation circuit 104 (shown in FIG. 1). In the hot water supply operation by the heat pump unit 500), the method of the present invention may be applied to switch the three-way valve 10D by the same method as described above. In this case, when the boiling pump 119 corresponding to the boiling pump 19 is controlled, it is provided at the outlet side of the water-side flow passage 115a of the water-refrigerant heat exchanger 115 instead of the boiling temperature Tb. The outlet temperature detected by the temperature sensor is used (see FIG. 11 (c)), and instead of the circulation flow rate V of the boiling pump 19, the heating circulation circuit 104 by the boiling pump 119 is used. The circulation flow rate of is associated.

  Further, for example, at least one of the two-way valves 121 and 122 may be replaced with an expansion valve having a closing function. Further, instead of the expansion valves 111 and 113, an ejector may be used as a pressure reducer.

1 Heat pump water heater (hot water storage type water heater)
2 Hot water tank 4,5 Hot water pipe 6d Pipe (medium temperature water return pipe)
6e piping (low temperature water return pipe)
8 Hot water discharge pipe 8b, 8d Pipe (medium-temperature water extraction pipe)
10D Switching valve 12 Hot water storage temperature sensor 14 Compressor 15 Water-refrigerant heat exchanger 15a Refrigerant-side flow path 15b Water-side flow path 17 Outdoor heat exchanger (heat pump heat exchanger)
18 Refrigerant piping 19 Boiling pump (circulation pump)
23 Inlet water temperature sensor 24 Boiling temperature sensor (boiling temperature detecting means)
25 Refrigerant piping 26 Refrigerant piping 27 Indoor heat exchanger (air heat exchanger)
30 Refrigerant circulation circuit 104 Heating circulation circuit (hot water circulation circuit)
105a piping (hot water piping)
106a piping (hot water piping)
114 Compressor 115 Water-refrigerant heat exchanger 115a Refrigerant-side flow passage 115b Water-side flow passage 117 Outdoor heat exchanger (air heat exchanger)
118 Refrigerant piping 119 Boiling pump (circulation pump)
130 Refrigerant circulation circuit 410B Compressor control unit (compressor control means)
440 Heat exchange control section 440A Pump control section (pump control means)

Claims (5)

Performing heat exchange between the refrigerant and water, a water-refrigerant heat exchanger that functions as a condenser,
Performing heat exchange between the refrigerant and air, an air heat exchanger functioning as an evaporator,
A compressor connected to the water-refrigerant heat exchanger and the air heat exchanger,
A hot water storage tank for storing hot water,
A hot water outlet pipe that is connected to the hot water storage tank and taps hot and cold water;
Have
The water side of the water-refrigerant heat exchanger and the hot water storage tank are annularly connected by a hot water pipe to form a hot water circulation circuit,
The refrigerant side of the water-refrigerant heat exchanger, the compressor, and the air heat exchanger, to form a refrigerant circulation circuit by connecting with a refrigerant pipe,
The inlet side of the water refrigerant heat exchanger communicates with the discharge side of the compressor, and the water refrigerant heat exchange with the inlet side of the air heat exchanger whose outlet side communicates with the suction side of the compressor. In the hot water storage type hot water supply device, which communicates with the outlet side of the water heater, and performs hot water supply processing for supplying hot water heated by the water-refrigerant heat exchanger to the hot water storage tank,
The tap pipe is
The hot water storage tank is connected to an intermediate portion in the vertical direction, and is provided with a medium-temperature water take-out pipe for taking out hot water from the hot water storage tank,
The hot water circulation circuit,
A low-temperature water return pipe connected to the lower part of the hot water storage tank to return hot water into the hot water storage tank;
A medium-temperature water return pipe in which the hot water storage tank side is connected to the medium-temperature water removal pipe, and hot water is returned to the hot-water storage tank via the medium-temperature water removal pipe;
Which is provided at a branch point between the low-temperature water return pipe and the medium-temperature water return pipe, and hot water from the water side of the water-refrigerant heat exchanger is introduced into either the low-temperature water return pipe or the medium-temperature water return pipe? Switchable switching valve,
Is equipped with
And,
The switching valve is switched so as to introduce the hot water into the low-temperature water return pipe until a predetermined period elapses after the start of the hot water supply process, and the predetermined period elapses after the start of the hot water supply process. After that, a hot water storage type hot water supply device is provided, which is provided with a return switching control means for switching so as to introduce the hot water into the medium temperature water return pipe. The water-refrigerant heat exchanger further has a boiling temperature detecting means for detecting the temperature of the hot water flowing from the water side to the hot water pipe,
The predetermined period is
The hot water storage type hot water supply apparatus according to claim 1, wherein the hot water storage type hot water supply apparatus has a period longer than an elapsed time after the start of the hot water supply process until the detected value of the boiling temperature detection means reaches a predetermined target value. The predetermined period is
The hot water storage type hot water supply apparatus according to claim 2, wherein after the start of the hot water supply process, the refrigeration cycle of the refrigerant flowing through the refrigerant circulation circuit is longer than the elapsed time until a stable timing at which the refrigerant can be regarded as stable. Compressor control means for controlling the rotation speed of the compressor,
A circulation pump for circulating the hot water in the hot water pipe,
Pump control means for controlling the number of revolutions of the circulation pump according to the deviation between the detection value of the boiling temperature detection means and the target value,
The stable timing is
The hot water storage type hot water supply apparatus according to claim 3, wherein the rotation speed of the circulation pump controlled by the pump control means is at a timing at which a predetermined threshold value or more is reached. The air heat exchanger,
An indoor heat exchanger that performs heat exchange between the refrigerant and indoor air,
And,
A heat pump heat exchanger that is connected in parallel to the water refrigerant heat exchanger with respect to the compressor and performs heat exchange between the refrigerant and the outside air,
Atmospheric exhaust heat cooling mode that communicates the inlet side of the heat pump heat exchanger with the discharge side of the compressor and communicates the outlet side of the heat pump heat exchanger with the inlet side of the indoor heat exchanger, and the compression Exhaust heat utilization for performing the hot water supply process by communicating the inlet side of the water-refrigerant heat exchanger with the discharge side of the machine and communicating the outlet side of the water-refrigerant heat exchanger with the inlet side of the indoor heat exchanger A mode switching means capable of switching between the cooling mode and
The hot water storage type hot water supply apparatus according to claim 4, further comprising:

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