JPS60165457A - Heat pump hot-water supplier - Google Patents

Abstract

PURPOSE:To improve the energy saving property of equipments and permit to obtain sufficient hot-water even when an atmospheric enthalpy is reduced by retrieving and re-utilizing heat from the hot-water after bathing by the heat pump. CONSTITUTION:First solenoid valve 18 is provided between the hot-water heat exchanger 4 of a refrigerant circuit 17 and an expansion valve 7 while a non- return valve 19 is provided between an evaporator 6 and an accumulator 8. Second solenoid valve 21, second expansion valve 24 and an evaporation heat exchanger 23 for hot- water, buried in a bathtub 16, are provided by branching between the hot-water heat exchanger 4 and the first solenoid valve 18 to constitute second refrigerant circuit 20 connected to the accumulator 8. Temperature in the bathtub 16 is detected after bathing to close the first solenoid valve 18, open the second solenoid valve 21, flow the refrigerant to the second refrigerant circuit 20 and effect waste heat utilizing operation for retrieving the heat from remaining hot-water in the bathtub 16 by the hot-water evaporation heat exchanger 23. When the temperature in the bathtub becomes lower than a predetermined value, the first solenoid valve 18 is opened, the second solenoid valve 18 is opened, the second solenoid valve 2 is closed and the device is operated by a normal heat pump cycle which obtains heat from atmosphere.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a heat pump water heater.

Conventional Structure and Problems A conventional heat pump water heater of this type is shown in FIG. In other words, 1 is a hot water tank covered with insulation material,
2 is a heat pump heat source unit, which detects the temperature at the outlet of the evaporator 6 using a compressor 3, a hot water heat exchanger 4 that acts as a condenser, and a thermosensor tube 5 to keep the degree of superheating of the refrigerant at the outlet of the evaporator 6 constant. The temperature-type automatic expansion valve 7 (
(hereinafter referred to as an expansion valve), an evaporator 6, and an aqueous emulator 8 are connected through a tubular refrigerant pipe. Further, 9 is a heat source blower device.

The hot water storage tank 1 and the heat exchanger 4 for enriched water in the heat pump heat source unit 2 are connected by a water circulation outgoing pipe 10 and a water circulation return pipe 11 to form a water circulation circuit.

Further, a pump 12 is provided in the water circulation outgoing pipe 10. 13 is a water supply pipe provided to the hot water storage tank 1 via a pressure reducing valve 14, and 15 is a hot water outlet through which hot water in the hot water storage tank 1 is discharged into the bathtub 16.

To explain the operation of the heat pump water heater having this configuration, the high-temperature, high-pressure gas refrigerant compressed by the compressor 3 exchanges heat with the water sent by the pump 12 from the hot water storage tank 1 in the hot water heat exchanger 4. , gives heat to water and condenses to become a liquid refrigerant. After that, it enters the expansion valve 7 and is depressurized, and in the evaporator 6 it absorbs heat from the outside air sucked in by the heat source blower 9 and evaporates to become a gas refrigerant. The gas refrigerant passes through the accumulation lake 8 and returns to the compressor 3. The water in the hot water tank 1 is heated by this heat pump cycle.

The hot water in the hot water storage tank 1 is guided into the bathtub 16 and used by opening the hot water outlet 15 during bathing.

Water is guided into the hot water tank 1 from the water supply port by the amount of hot water used.

Here, the hot water in the bathtub 16 is only thrown away after bathing or used for washing, etc., and even though the hot water left after bathing has a high calorific value, it is not used effectively. When the enthalpy decreases, the amount of heat absorbed by the evaporator 6 decreases, causing problems such as not being able to produce sufficient hot water.

OBJECTS OF THE INVENTION The present invention aims to solve these conventional problems, and aims to efficiently pump and reuse heat from hot water after bathing using a heat pump.

Structure of the Invention In order to achieve this object, the present invention provides a first electromagnetic valve between a hot water heat exchanger and an expansion valve in a conventional refrigerant circuit, and a check valve between an evaporator and an aqueous emulator. branching from between the heat exchanger and the first solenoid valve, a second solenoid valve, a second solenoid valve, and a second solenoid valve.
An expansion valve and a hot water evaporative heat exchanger buried in the bathtub are provided to form a second refrigerant circuit leading to the accumulator.

With this configuration, the temperature inside the bathtub is detected after bathing, and the first
The solenoid valve is closed, the second solenoid valve is opened, the refrigerant is flowed through the second refrigerant circuit, and the hot water evaporative heat exchanger performs exhaust heat utilization operation in which heat is pumped up from the remaining hot water in the bathtub, and the temperature inside the bathtub is lowered. When the temperature falls below a predetermined value, the first solenoid valve is opened, the second solenoid valve is closed, and the heat pump operates in a normal heat pump cycle that pumps heat from outside air.

As a result, heat can be effectively extracted from the hot water in the bathtub after bathing, and the energy saving performance of the device is improved.

DESCRIPTION OF THE EMBODIMENTS The structure of an embodiment of the present invention will be described below with reference to FIG. Note that the same numbers as in FIG. 1 indicate the same members.

In FIG. 2, the conventional refrigerant circuit is a first refrigerant circuit 17, 18 is a first solenoid valve provided between the expansion valve 7 of the first refrigerant circuit 17 and the hot water heat exchanger 4, and 19 is an evaporator. 6 and the accumulator 8. 20 is a second refrigerant circuit that branches from between the hot water heat exchanger 4 and the first solenoid valve 18 and extends between the first check valve 19 and the accumulator 8, and the second refrigerant circuit includes two solenoid valves in order from the branch. 21. A second expansion valve that detects the temperature at the outlet 1 of the hot water evaporative heat exchanger 23 using a temperature sensing cylinder 22 and adjusts the opening degree so that the degree of superheating of the refrigerant at the outlet of the hot water evaporative heat exchanger 23 is constant. 24, a hot water evaporative heat exchanger 23 and a second check valve 25 buried in the bathtub 16 are provided.

26 detects the temperature of the water in the bathtub 16 and connects the first electromagnetic J"
18, a temperature sensor that switches the second electromagnetic valve 21;

Reference numeral 27 denotes a temperature detector that detects the temperature of hot water in the hot water storage tank 1 and turns on and off the equipment.

FIG. 3 shows an electric circuit diagram, in which a relay coil 30 is provided in parallel between the power lines 28 and 29, a temperature sensor 26 for detecting bath water temperature that energizes the relay coil 30, and a switch 31 in series with the temperature sensor 26. ing. Similarly, power line 28
．． A relay contact 32 is provided in parallel between the power lines 28 and 29, and a second solenoid valve 21 that is activated when the relay contact 32 is turned on is provided. Similarly, a relay contact 33 is provided in parallel between the power lines 28 and 29, and a fan contact 34 is provided in series with the relay contact 33. and said relay contact 3
3. The first solenoid valve 18 that operates when the fan contact 34 is turned on.
, a heat source blower 9 is provided. Relay contacts 32 and 33 are reverse contacts. Further, a compressor contact 35 and a compressor 3 and a pump 12, which are operated when the compressor contact 35 is turned on, are provided in parallel between the power supply lines 28 and 29. Similarly, a temperature detector 27 that detects the temperature of hot water in the hot water storage tank 1 and a temperature
A relay coil 36 is provided which is energized when the detector 27 is activated.

When the relay coil 36 is energized, the compressor contact 35 and the fan relay contact 34 are turned on.

Next, to explain the operation, as shown by the solid line in the figure, during normal operation, the temperature detector 27 detects the temperature inside the hot water storage tank 1, and if the temperature is below a predetermined value, the relay coil 36 is energized and the compressor contacts are 35, fan contact 34 is turned on. Further, since the switch 31 is off and the V-coil 30 is not energized, the relay contact 32 is off, the relay contact 33 is on, and the second electromagnetic valve is closed. Therefore, the compressor 3, pump 12, and heat source blower 9 are driven, and the first solenoid valve is opened, and the refrigerant flows into the first refrigerant circuit 17 as in the conventional case, and the heat of the outside air pumped by the evaporator 6 is absorbed. Heat exchanger for hot water 4
It exchanges heat with the water in the hot water tank 1 and heats the water in the hot water tank 1 to a predetermined temperature.

When the temperature reaches a predetermined temperature, the relay coil/I'36 is de-energized by the temperature detector 27, the contacts 35 and 36 are turned off, the compressor 3, the pump 12, and the heat source blower 9 are stopped, and the first
Solenoid valve 18 is closed. Next, when taking a bath, the hot water outlet 16 is opened and hot water from the hot water tank 1 is introduced into the bathtub 16 and used. Further, water is replenished into the hot water storage tank 1 from the water supply port 13 according to the amount used.

Since a large amount of hot water is used when taking a bath, a temperature sensor 2 is used.
7 is below the predetermined value, and normal heat pump operation using the heat from outside air is performed even when hot water is being used.

Next, during exhaust heat utilization operation, after taking a bath, turn on the switch 31 without throwing away the remaining hot water in the bathtub 16, and if the temperature sensor 26 for detecting the bathtub water temperature is activated and the temperature exceeds a predetermined value, the relay coil/l'
30 is energized, the relay contact 32 is turned on, and conversely, the relay contact 33 is turned off and the second solenoid valve is opened. Here, the device is performing normal heat pump operation and the relay contact 33 is in the OFF state, so the first solenoid valve 18 is closed and the heat source blower 9 is also stopped.

As a result, as shown by the dotted line arrow in FIG. It is heated and condensed to become a liquid refrigerant, which enters the second refrigerant circuit 20. Thereafter, the water passes through a second electromagnetic valve, is depressurized by a second expansion valve 24, and enters a hot water evaporative heat exchanger 23 buried in the bathtub 16. The hot water evaporative heat exchanger 23 removes heat from the remaining hot water and evaporates it to become a gas refrigerant. The gas refrigerant passes through the second check valve 25 and the achievator 8 and returns to the compressor 3. Through this cycle, the heat of the remaining hot water in the bathtub 16 can be applied to the water in the hot water storage tank 1. Here, the first solenoid valve 18 is closed, and the evaporator 6 is separated by the first solenoid valve 18 and the first check valve 19, so there is no accumulation of refrigerant. When the temperature inside the bathtub 16 falls below a predetermined value, the temperature detector 26 is activated, the relay coil/L'30 is de-energized, the relay contact 32 is turned off, and the relay contact 33 is turned on. Therefore, the second electromagnetic valve 21 is closed, the first electromagnetic valve 18 is opened, and the heat source blower 9 is also driven to perform the normal heat pump operation that removes heat from the outside air. The heat pump is operated to heat the water in the hot water tank 1 to a predetermined temperature as measured by the temperature sensor 27. At this time, the hot water evaporative heat exchanger 23 is separated by the second solenoid valve 21 and the second check valve 26 . After the water is heated, the switch 31 is turned off.

In this way, after taking a bath, the temperature inside the bathtub is detected, the first solenoid valve 18 is closed, the second solenoid valve 21 is opened, and the refrigerant flows through the second refrigerant circuit 20, and the hot water evaporative heat exchanger 23 cools the bathtub. Because it removes heat more effectively than the remaining hot water, it can be operated in a highly efficient heat pump cycle.

Therefore, a highly energy-saving heat pump water heater can be provided.

Effects of the Invention According to the heat pump water heater of the present invention, the following effects can be obtained.

(1) A first solenoid valve is installed between the heat exchanger and the expansion valve in the refrigerant circuit of a conventional heat pump water heater, and the evaporator and the accumulation V-
A check valve is provided between the hot water heat exchanger and the first solenoid valve, and a 27th solenoid valve, a second expansion valve,
An evaporative heat exchanger for hot water buried in the bathtub is installed to form a second refrigerant circuit leading to the accumulator.After bathing, the temperature inside the bathtub is detected, the first solenoid valve is closed, and the second solenoid valve is opened. By flowing the refrigerant into the second refrigerant circuit and performing an exhaust heat utilization operation that pumps up heat from the remaining hot water in the bathtub using the -9 hot water evaporative heat exchanger, heat can be extracted not only from the outside air but also from the high calorific value of the remaining hot water. It is possible to provide a heat pump hot water supply device that can be operated in a heat pump cycle with high efficiency and has no accumulation of refrigerant and is highly energy saving.

2) In conventional heat pump water heaters that take heat from outside air, when the outside air enthalpy decreases, the amount of heat absorbed by the evaporator decreases, and there is no longer an opening point where a sufficient amount of hot water cannot be obtained within a certain amount of time. , ensuring a satisfactory amount of hot water.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a conventional heat pump water heater, FIG. 2 is a block diagram of a heat pump water heater according to an embodiment of the present invention, and FIG. 3 is an electric circuit diagram of the heat pump water heater. 3... Compressor, 4... Condenser (hot water heat exchanger), 6... Evaporator, 7... First throttle mechanism (first 1 expansion valve), 8... accumulator, 17... first refrigerant circuit, 18...
...First solenoid valve, 19...First check valve, 20.
...Second refrigerant circuit, 21...Second solenoid valve, 23...Evaporative heat exchanger for hot water, 24...
...Second throttle mechanism (second expansion valve), 25...Second check valve.

Claims (1)

[Claims] (1) A first refrigerant circuit in which a compressor, a condenser, a first solenoid valve, a first throttle mechanism evaporator, a check valve, and an accumulator are connected through annular pipes, and between the condenser and the first solenoid valve. A heat pump hot water supply device in which a second refrigerant circuit that branches out from the accumulator is provided with a second electromagnetic valve, a second throttle mechanism, and a hot water evaporative heat exchanger buried in the bathtub. (2) The heat pump water heater according to claim 1, wherein the heat pump water heater is configured to detect the temperature inside the bathtub and selectively switch between the first refrigerant circuit and the second refrigerant circuit using the first solenoid valve and the second solenoid valve. (2) The heat pump water heater according to claim 2, wherein the second refrigerant circuit is activated when the bathtub temperature is above a predetermined value, and the first refrigerant circuit is activated when the temperature within the bathtub is below a predetermined value.