JP2009103446A - Heat pump water heater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat pump water heater capable of preventing hot water shortage by always allowing discharge of hot water maintained at a set temperature from a mixing valve even when hot temperature water in a hot water storage tank is used in large amounts for bath and on a faucet side. <P>SOLUTION: The heat pump water heater includes a heat pump heating device 4, piping in which water heated by the heat pump heating device 4 flows, and switching means (13, 14) for switching between piping FP1 for leading the heated water to the hot water storage tank 1, and pipes (FP4a, FP2) leading the heated water to the mixing valve 11. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a heat pump water heater for boiling water in a hot water storage tank.

  FIG. 5 is a system configuration diagram showing a conventional heat pump water heater. In FIG. 5, 1 is a hot water storage tank, 2 is a heating element provided in the hot water storage tank 1 for heating water, and 3 is attached to an outer wall portion below the hot water storage tank 1 to control the temperature of water in the tank 1. It is a temperature detector to detect. 4 is a heat pump type heating device that heats the water in the hot water storage tank 1, and is composed of a refrigerant circuit in which a compressor 5, a condenser 6, a pressure reducing device 7, and an evaporator 8 are sequentially connected.

  Further, a circulation pump 9 that circulates water through a pipe connected to a condenser 6 that constitutes the heat pump type heating device 4 and a flow rate adjustment valve 10 that adjusts the circulation flow rate of water are provided. Furthermore, a mixing valve 11 is provided via a pipe connected to an outlet located above the hot water storage tank 1. Reference numeral 12 denotes a control unit that intermittently operates the heating element 2, the heat pump type heating device 4, and the circulation pump 9 based on the output from the temperature detector 3.

  Next, the heating operation of the heat pump water heater having such a configuration will be described with reference to the system configuration diagram shown in FIG. After water is supplied into the hot water storage tank 1 from the lower part to reach a full tank state, the boiling operation is started. Thereby, the compressor 5 starts operation, and the compressed primary refrigerant gas flows toward the condenser 6 through the pipe. Then, the pressure of the primary refrigerant gas coming out of the condenser 6 is lowered by the decompression device 7, and the secondary refrigerant gas maintained at the low pressure level flows toward the evaporator 8. Due to the refrigerant flow, the condenser 6 side is in a high temperature state and the evaporator 8 side is in a low temperature state. Next, the water in the hot water storage tank 1 escapes from the lower part thereof, passes through the flow rate adjustment valve 10 from the circulation pump 9, and enters the central part of the hot water storage tank 1 through the condenser 6 maintained at a high temperature.

  Then, the water in the hot water storage tank 1 again escapes from the lower portion, passes through the condenser 6 from the circulation pump 9 and enters the central portion of the hot water storage tank 1. By such a water circulation operation, the water in the hot water storage tank 1 passes through the condenser 6 and is heated to a predetermined temperature, and is stacked from above in the hot water storage tank 1 due to a temperature difference with the water. The heating element 2 is provided in order to prevent the condenser 6 from being heated due to a failure of the compressor 5 or the like, or being unable to supply predetermined high-temperature water due to the outside air temperature. Next, high-temperature water is produced in the hot water storage tank 1, and the high-temperature water is directed to the high-temperature water side (A part in FIG. 5) of the mixing valve 11, and the water from the water source is the low-temperature water side of the mixing valve 11. (B section in FIG. 5). And the warm water of an appropriate temperature state is made with the mixing valve 11, and is supplied to the bathtub side or the faucet side, for example.

  A conventional heat pump water heater has a system configuration in which hot water is stored in a hot water storage tank as described above and hot water discharged from a mixing valve is supplied to a bathtub side and a faucet side as needed. However, when a large amount of hot water in the hot water storage tank is used, for example, on the bathtub side or faucet side, water corresponding to the amount used is supplied into the hot water storage tank. As a result, the temperature of the high-temperature water in the hot water storage tank is lowered, and there arises a problem that hot water lower than the set temperature is discharged from the mixing valve, that is, “hot water out”.

  The present invention has been made to solve the above-described problems. Even when a large amount of high-temperature water in the hot water storage tank is used on the bathtub side or the faucet side, the mixing valve is always kept at the set temperature. The purpose is to prevent “hot water out” by allowing hot water to come out.

  A heat pump type heating device, a pipe for guiding water to the hot water storage tank through a mechanism heated by the heat pump type heating device, and a pipe for guiding water from the hot water storage tank, or a pipe for guiding water from the hot water storage tank or a heat pump type One of the pipes for guiding water to the hot water storage tank through the mechanism heated by the heating device is led to the mixing valve.

  A heat pump type heating device, a pipe for guiding water to the hot water storage tank through a mechanism heated by the heat pump type heating device, a temperature detector for detecting the temperature of the hot water storage tank, and a pipe for guiding water from the hot water storage tank Based on the detection result of the temperature detector, either one of the pipe for guiding water from the hot water storage tank or the pipe for guiding water to the hot water storage tank through a mechanism heated by a heat pump type heating device is guided to the mixing valve. I made it.

  Since the heat pump water heater of the present invention is configured as described above, it is possible to prevent “hot water out”.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a system configuration diagram showing Embodiment 1 according to a heat pump water heater of the present invention. FIG. 3 is another system configuration diagram showing the first embodiment. FIG. 3 is a flowchart showing a flow of operation of the system configuration in the first embodiment. FIG. 6 is still another system configuration diagram showing the first embodiment. It is a system block diagram of the conventional heat pump water heater.

Embodiment 1 FIG.
1 and 2 are system configuration diagrams showing Embodiment 1 according to the heat pump water heater of the present invention, and FIG. 3 is a flowchart showing an operation flow of the system configuration. 1 and 2, the same reference numerals as those in the conventional example indicate the same or corresponding parts. Reference numeral 13 denotes a first electric switching valve connected via a pipe between the central portion of the hot water storage tank 1 and the condenser 6, and reference numeral 14 denotes an outlet portion of the hot water storage tank 1 and the hot water side of the mixing valve 11 (FIGS. 1 and 2). 2 between the water source side and the low temperature water side of the mixing valve 11 (D portion in FIGS. 1 and 2). It is the 3rd electric switching valve connected via piping.

Next, the heating operation of the heat pump water heater will be described with reference to the system configuration diagram shown in FIGS. 1 and 2 and the flowchart shown in FIG. In FIG. 1, when water is supplied from the lower part in the hot water storage tank 1 and the boiling operation is started after reaching the full tank state (step S100), the condenser 6 is heated and the circulation pump 9 is A series of operations for circulating the water in the hot water storage tank 1, that is, a boiling operation is executed (step S101). Thereby, the water in the hot water storage tank 1 flows out from the lower part to the first flow path FP ₁ and flows from the circulation pump 9 toward the flow rate adjusting valve 10. Then, the water passes through the condenser 6 in a high temperature state and enters from the central portion of the hot water storage tank 1 through the OUT side from the IN side of the first electric switching valve 13. Thereafter, the above-described operation content is repeated.

Next, to detect the temperature Ts boiling in the process of heating by circulating water in such hot water storage tank 1 (step S102), whether the control unit 12 boiling temperature Ts has reached a predetermined temperature T ₁ of example 90 ° C. Is determined (step S103). Here, if NO, that is, the boiling temperature Ts does not reach the predetermined temperature T ₁ , the above operation is repeated. Further, if the temperature Ts boiling. If YES reaches the predetermined temperature T _1, as well as controls the condenser 6 to be kept at that temperature T _1, "water out" operation of prevention is started (Step S104). In this process, high-temperature water corresponding to 90 ° C. in the hot water storage tank 1 escapes from the outlet to the second flow path FP _2, and the high temperature of the mixing valve 11 passes from the IN side to the OUT side of the second electric switching valve 14. water side to the (C portion in FIG. 1), the water from the water source cold water side of the mixing valve 11 through the OUT side from the iN side of the third electric switching valve 15 by the third flow path FP ₃ (in FIG. 1 To D part).

Next, the control unit 12 boiling temperature Ts to determine whether it is less than the predetermined temperature T ₂ for example 80 ° C. (step S105). Note that the predetermined temperature T ₂ is a temperature threshold that assumes that the remaining hot water in the hot water storage tank 1 flows into the mixing valve 11 and that the hot water discharged from the mixing valve 11 is just before “hot water out”. Here, if NO, that is, if it is determined that the boiling temperature Ts is not 80 ° C. or less, the additional boiling operation by the condenser 6 is not started. Further, if YES, that is, if it is determined that the boiling temperature Ts is 80 ° C. or less, the user uses a large amount of high-temperature water in the hot water storage tank 1 on the bathtub side or the faucet side, thereby causing “hot water out”. It is determined that there is a high possibility that it will occur, and the additional boiling operation by the condenser 6 is executed (step S106). In addition, it is impossible to maintain the temperature of the high-temperature water at 90 ° C., and it is assumed that the temperature is lower than that.

Next, as shown in FIG. 2, the first electric switching valve 13 and the second electric switching valve 14 are switched (step S107), and the water from the water source is maintained in a high temperature state from the circulation pump 9 through the flow rate adjusting valve 10. It flows toward the condenser 6 to be used. The high-temperature water heated by the condenser 6 passes from the IN side of the first electric switching valve 13 to the 4th flow path FP _4a through the OUT side, and further from the IN side to the OUT side of the second electric switching valve 14. Flows to the high temperature water side of the mixing valve 11 (C section in FIG. 2). At this time, water from the water source flows from the IN side of the third electric switching valve 15 to the low temperature water side (D portion in FIG. 2) of the mixing valve 11 through the OUT side. Hot water is poured out.

Next, the control unit 12 determines whether or not the user has entered a time zone in which the hot water in the hot water storage tank 1 is hardly used, that is, a midnight time zone (step S108). Here, if NO i.e. temperature Ts boiling if outside midnight time zone to determine whether it is less than the predetermined temperature T ₂ (step S105). The subsequent steps are the same as described above. If YES, that is, in the midnight time zone, the first electric switching valve 13 and the second electric switching valve 14 are switched to the state shown in FIG. 1 (step S109). Then, a boiling operation is performed in which the hot water in the “hot water out” state in the hot water storage tank 1 is returned to the hot water storage tank 1 through a condenser 6 that maintains a high temperature state through a predetermined flow path at midnight. (Step S101). As a result, the hot water can be stored again in the hot water storage tank 1.

  When the heat pump water heater having such a configuration determines that there is a high possibility that the user will use a large amount of high-temperature water in the hot water storage tank 1 to cause “hot water out”, the high-temperature water that has passed through the condenser 6 is used. By flowing directly to the high temperature water side of the mixing valve 11 without returning to the hot water storage tank 1, the situation of "hot water out" can be prevented. Since it is easy to prevent “hot water out” without increasing the size of the hot water storage tank 1, the heat pump water heater is easier to reduce the size and save energy than when the hot water storage tank is increased in size. It is easy to reduce the load on the environment.

In the process of determining whether or not the boiling temperature Ts is equal to or lower than the predetermined temperature T ₂ (step S105), if there is a high possibility of causing YES, that is, “hot water out”, as shown in FIG. The first electric switching valve 13 and the third electric switching valve 15 are switched. Then, the high-temperature water that has passed through the condenser 6 passes from the IN side of the first electric switching valve 13 to the fourth flow path FP _4b through the OUT side, and further from the IN side to the OUT side of the third electric switching valve 15. And flow. Next, the high-temperature water is allowed to flow to the low-temperature water side (D portion in FIG. 4) of the mixing valve 11, while the high-temperature water in the hot water storage tank 1 is allowed to pass from the IN side to the OUT side of the second electric switching valve 14. It may be configured to flow to the high temperature water side (C portion in FIG. 4) of the mixing valve 11.

DESCRIPTION OF SYMBOLS 1 Hot water storage tank, 2 Heat generating body, 3 Temperature detector, 4 Heat pump type heating device, 5 Compressor, 6 Condenser, 7 Decompression device, 8 Evaporator, 9 Circulation pump, 10 Flow control valve, 11 Mixing valve, 12 Control 13, the first electric switching valve, 14 the second electric switching valve, 15 the third electric switching valve, FP ₁ first flow path, FP ₂ second flow path, FP ₃ third flow path, FP _4a 4a channel, FP _4b 4b channel.

Claims (4)

A hot water storage tank,
A heat pump heating device;
Piping through which the water heated by the heat pump heating device flows;
Switching means for switching between a pipe for guiding the heated water to the hot water storage tank and a pipe for guiding the heated water to a mixing valve;
Heat pump water heater equipped with. A hot water storage tank,
A heat pump heating device;
Piping through which the water heated by the heat pump heating device flows;
Switching means for switching between a pipe for guiding the heated water to the hot water storage tank and a pipe for guiding the heated water to a mixing valve;
A temperature detector for detecting the temperature of the hot water storage tank;
With
A heat pump water heater, wherein the switching means is operated based on a detection result of the temperature detector. A hot water storage tank,
A first flow path for circulating water in the hot water storage tank;
A circulation pump provided in the first flow path;
A heat pump heating device that heats the circulating water in the middle of the first flow path;
A second flow path for supplying hot water stored in the hot water storage tank to the hot water side of the hot water mixing valve;
A third flow path for supplying low temperature water from the water source side to the low temperature water side of the hot water mixing valve;
In the heat pump water heater with
A first electric switching valve provided in the first flow path;
A second electric switching valve provided in the second flow path;
A third electrically operated switching valve provided in the third flow path;
A fourth flow path connecting the first electric switching valve and the second electric switching valve;
A fifth flow path connecting the first electric switching valve and the third electric switching valve;
With
The water heated by the heat pump heating device passes through the first electric switching valve, the fourth flow path, and the second electric switching valve from the first flow path. Flowing from the flow path to the hot water mixing valve,
Flowing from the first flow path to the hot water storage tank via the first electric switching valve,
A heat pump water heater characterized by being switched. A temperature detector for detecting the temperature of the hot water in the hot water storage tank;
A control unit for controlling the first to third electric switching valves;
Further comprising
The control unit controls the first to third electric switching valves based on the output from the temperature detector, and the high-temperature water heated by the heat pump heating device is transferred from the first flow path to the first flow path. Flowing from the second flow path to the hot water mixing valve via the first electric switching valve, the fourth flow path, and the second electric switching valve;
From the first flow path to the hot water storage tank via the first electric switching valve,
The heat pump water heater according to claim 3, wherein the heat pump water heater is switched.

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