JPS58129164A - Hot-water supply device for heat pump - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat pump water heater, and more particularly to a heat pump water heater that uses a mixed refrigerant and can supply hot water of about 70°C, which is required in ordinary households, without having to set a particularly large compression ratio t. It is something.

Conventionally, in heat pump water heaters that use outside air as a heat source and heat dissipation from the refrigeration cycle to supply hot water, the working fluid (
Since a gas-liquid phase change sound mono-composition refrigerant or an azeotropic mixed refrigerant is used as a cold IJE, when trying to obtain hot water from a water temperature as low as 15°C to as high as 70°C. had drawbacks such as an increase in Shimada pressure and a decrease in heating capacity depending on the refrigerant used.

For example, when heat pump water supply is performed using the CFC refrigerant R-22, which is currently widely used in home air conditioners, the saturation pressure at the condensation temperature of R-22 of 70°C is 3.
0, “kg’em” qb*, so 20i, 9”7c
At present, the maximum pressure for normal use is σ) compressor, which cannot be used.

Also, fluorocarbon refrigerant R-12, which is widely used in household refrigerators and general cold storage. When ζ-thombu hot water is used as a production kIJ fluid, the temperature of R-12 is 70℃.
The saturation pressure at is 19, "!1/crn" abs, so there is no problem in terms of pressure, but the evaporation pressure becomes lower, the compression ratio increases, the volumetric efficiency of the compressor decreases, and the specific volume of the refrigerant also increases. Therefore, the heating capacity was reduced by 30% or more compared to R-22. Therefore, in order to increase the heating capacity, it was necessary to increase the displacement of compressed ginseng.

It is generally known that the lower the boiling point of the refrigerant, from R-12 to R-22, the greater the capacity in the same refrigeration cycle.
This results in an increase in the saturation pressure at °C, making it difficult to satisfy both requirements using a mono-composition refrigerant or an azeotropic refrigerant mixture.

The purpose of the present invention is to eliminate the drawbacks of the prior art, and to increase the condensing pressure (high pressure) to supply hot water of about 70°C, which is necessary for households.
The purpose of the present invention is to provide a heat pump water heater that can suppress the reduction in heating capacity and supply efficient water supply with a rod-shaped compressor.

In order to achieve the above object, the present invention uses a non-azeotropic mixed refrigerant in which the two components of a high boiling point and a low boiling point are mixed in an appropriate ratio as a component (refrigeration) of a heat pump cycle. The first heat exchanger for hot water supply mainly condenses high boiling point refrigerant, passes through a gas-liquid separator 1 to separate gas and liquid, and separates the separated gas 2 Mainly low boiling point refrigerant used in heat exchangers for hot water supply? The refrigerant is designed to condense, suppressing the rise in high pressure when hot water is supplied at 70°C, and is equipped with two outdoor heat exchangers. In the heat exchanger, the low boiling point refrigerant mainly evaporates and absorbs heat to increase the evaporation pressure and heating capacity.

The invention will be explained below based on examples.

FIG. 1 shows an embodiment of the heat pump supply device of the present invention. In the figure, 1 is a hot water storage tank, 2 is an outdoor Yuekoto, and 3 is a hot water storage tank.
This is a heat exchanger for hot water supply which has the functions of a ti compressor and a 4 to 1lciiS unit. It consists of two water heat exchangers connected in series with q 4g and 4b.

A gas-liquid separator 5 is arranged between the heat exchangers 4a and 4b for water supply and hot water. 6 is an outdoor heat exchanger 60 having a machine II'@t as an evaporator, and 7.7α is a pressure reducer (e.g. capillary lift), which connects a compressor 5, a hot water supply heat exchanger 4, and an indoor heat exchanger 60. Together with the outer heat exchanger 6, it constitutes a refrigeration cycle. The water piping around the hot water storage tank 1 (indicated by broken lines) includes a water supply valve 8, a pressure reducing check valve 9, and a pump 10 that circulates the water in the hot water storage tank 1 through a hot water supply heat exchanger 41 to the upper part of the hot water storage tank. , 11 is a hot water supply pipe, 12 is a hot water tap, 13 is a heat exchange return pipe, 14 is a safety valve, 15 is a drain plug, 16 is a drain pipe, and 17 is a drain ditch. The refrigerant used in the above configuration is not a single composition fluid as in the past, but a non-azeotropic mixed refrigerant that is a mixture of a plurality of refrigerants with different properties. For example, a mixed refrigerant of R-12, which has a high boiling point and relatively low refrigerating capacity, and R-22, which has a low boiling point and relatively large capacity, is used.

Next, the heat pump hot water supply operation method will be explained.

The refrigerant pipe pressurized by the compressor 3 is transferred to the hot water supply heat exchanger 4α for heat exchange, and the metal gas-liquid separator 5 separates the refrigerant from gas to liquid. ?
This gas cooling is divided into parts and used in the hot water heat exchanger AbIL.
delivery, and the other liquid-cooled at cavity cavity 7a (
This is sent to the pressure reducer 7 through a slight resistance (which is enough to compensate for the piping pressure loss in the hot water supply heat exchanger 4b).

The refrigerant that has been heat exchanged and liquefied in the hot water supply heat exchanger 4b is also uniformly sent to the pressure reducer 7, where it is depressurized and cooled down to the outdoor heat exchanger 6.
to be transferred to. Here, the refrigerant absorbs heat from the outside air, evaporates, and is sucked into the compressor 5 in a gaseous state.

Here, the flow direction of the refrigerant and the water that is the heating medium in the hot water supply heat exchanger 444b is countercurrent. Therefore, the water in the hot water storage tank 1, which is initially low in temperature, is sent to the hot water supply heat exchanger 4b by the pump 10, heated and raised in temperature, and then sent to the hot water supply heat exchanger 4a for heat exchange. The hot water is stored in the hot water storage tank 1.Comparing the condensing temperature pipes of the two hot water heat exchangers 4a and 4b, the hot water heat exchanger 4α has a higher condensation temperature than the hot water heat exchanger 4b.However, Therefore, the refrigerant used in the heat pump cycle is a non-azeotropic mixed refrigerant having a high boiling point (e.g. R-12) and a low boiling point (e.g. R-22). It enters the exchanger 4α, and because of its high condensing temperature, R-12, which has a high boiling point, is mainly condensed.Then, it enters the gas-liquid separator 5, where the gas refrigerant that does not condense is separated and used for hot water supply with a low condensing temperature. Since the water is sent to the heat exchanger 4b, R-22 having a low boiling point is mainly condensed in the hot water supply heat exchanger 4b.

Even when hot water is supplied at a high temperature of about 0°C in the above area, the pressure on the high pressure side is 19.9°C, which is the saturation pressure at the condensation temperature of R-12 of 70°C, because R-12, which is a high boiling point refrigerant, is mainly condensed in the hot water supply heat exchanger 4g. To 2! i/crt? (!, it will be about 6#.

Next, consider heat absorption in the outdoor heat exchanger 6, which is the heat source side. After condensation, the mixed refrigerant of high boiling point and low boiling point is transferred to the pressure reducer 7.
It is then depressurized and cooled down to enter the outdoor heat exchanger 6.
Since the refrigerant is a mixed refrigerant, the evaporation pressure (compressor suction pressure) at this time is intermediate between the saturated pressure of the high boiling point and low boiling point of a single composition for the same evaporation temperature. Therefore, high boiling point refrigerant R-1
2 as the working fluid, the evaporation pressure increases, the compression ratio decreases, and the volumetric efficiency of the compressor improves. Furthermore, since the specific volume of the refrigerant also decreases, the heating capacity also increases.

In this way, the present invention eliminates the drawbacks of conventional single-component refrigerants, and improves the heating ability even in high-temperature (70°C) hot water supply by suppressing the condensing pressure (high pressure) in the riser tube and reaching the bulk compressor. This allows you to efficiently obtain high-temperature hot water.

FIG. 2 is a heat pump water heater showing another embodiment of the present invention, which is intended to improve the efficiency of the outdoor heat exchanger shown in FIG. In FIG. 2, the hermitages with the same numbers as in FIG. 1 have the same parts and have the same functions. The configuration in Figure 2 differs from Figure 1 in the heat exchanger on the heat source side, where the liquid refrigerant with a high proportion of low boiling point R-12 separated by the gas-liquid separator 5 and the heat exchanger for hot water supply are used. The liquid refrigerant having a high proportion of high boiling point refrigerant R-22 exiting the refrigerant 4b is decompressed and cooled in each separate pressure reducer 7, and enters the separate outdoor heat exchanger 6 6b, where it absorbs heat from the outside air. It vaporizes and is sucked into the pressure gas 3 in a gaseous state.

Therefore, in the outdoor heat exchanger 6cL, mainly high boiling point R-
In the outdoor heat exchanger 6h, mainly R-22 having a low boiling point evaporates and absorbs heat.

Here, the ventilation by the blower 60 is moved from the outdoor heat exchanger No. 6 to the outdoor heat exchanger 6 as shown by the arrow in the figure.
k. Therefore, the air that has been cooled by heat exchange in the outdoor heat exchanger No. 4 is further heat exchanged in the outdoor heat exchanger 6b. Comparing the evaporation temperatures of the two outdoor heat exchangers 6m and 6, the outdoor heat exchanger 6α has a higher evaporation temperature than the outdoor heat exchanger 6b. However, in the outdoor heat exchanger 6g, R-12 with a high boiling point mainly evaporates, and in the outdoor heat exchanger 6, R-2 with a low boiling point evaporates.
Since 2 is evaporated, the evaporation pressure can be made higher than in the case where both are mixed and heat is absorbed by evaporation as shown in FIG. Note that the cavity 7b provided at the outlet of the outdoor heat exchanger 6b is used especially when two refrigerants with widely different evaporation temperatures for the same pressure are used as working fluids. , 4b, the difference in evaporation temperature of the internal heat exchanger is compensated for by a certain limit. Heat exchanger for hot water supply 4&,
Since the action of 4h is the same as that shown in FIG. 1, a complete explanation will be omitted.

As described above, by dividing the outdoor heat exchanger into two parts and effectively utilizing the characteristics of the high boiling point and low boiling point mixed refrigerant, it is possible to increase the evaporation pressure and absorb heat from the outside air in an ideal manner. can.

As explained in the above examples, conventional heat pump water heaters use a single composition refrigerant or an azeotropic mixture refrigerant as the working fluid of the heat pump cycle. However, in each of the above-mentioned embodiments, a non-azeotropic mixed refrigerant in which at least two refrigerants of low boiling point and high boiling point are mixed in an appropriate mixing ratio is used as the working fluid. The heat exchanger is divided into two parts: a first hot water supply heat exchanger that mainly condenses a high boiling point refrigerant, and a second hot water supply heat exchanger that mainly condenses a low boiling point refrigerant, and both are placed in series to generate countercurrent heat to the water. By exchanging the hot water, the high pressure rise during hot water supply at high temperature (70°C) can be suppressed. Furthermore, the outdoor heat exchanger is used as a first outdoor heat exchanger in which high boiling point refrigerant evaporates, and a second outdoor heat exchanger in which low boiling point refrigerant evaporates. The air blowing configuration is such that the air is divided into two outdoor heat exchangers, and the air that has undergone heat exchange in the first outdoor heat exchanger is then heat exchanged in the second outdoor heat exchanger. By taking advantage of the characteristics of high boiling point and low boiling point refrigerants, heat can be efficiently absorbed from the outside air and the evaporation pressure can be increased, reducing compression waste and improving heating capacity, making the compressor more spacious. 70℃ required in house II without structural changes
It has an excellent practical effect of easily realizing a certain amount of hot water supply.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of a heat pump water heater of the present invention, and FIG. 2 is a block diagram of a heat pump water heater showing another embodiment of the present invention. 2...Outdoor unit 5...To compressor 444b...Hot water supply heat exchanger 5...To gas-liquid separator 6.66b...Outdoor heat exchanger 7.7tL, 7b...・Pressure reducer (capillary tube)
10... Pump agent patent attorney Usui Shitaku 167- Oh II! 1 4 piece 2 mountain

Claims (1)

[Scope of Claims] In a heat pump water supply system equipped with a compressor, a heat exchanger for hot water supply, an outdoor heat exchanger, and a pressure reducer, the non-azeotropic mixed refrigerant/medium at an appropriate mixing ratio is used as described above. In addition to being used as the working fluid of the device, the hot water supply heat exchanger'f is divided into two parts, each of which is used for countercurrent heat exchange and exchange with water, the first heat exchanger for hot water supply and the second heat exchanger for hot water supply. A gas-liquid separator is placed between the heat exchangers to separate the gas-liquid. A heat pump characterized in that the gas refrigerant separated by the separator flows into a second heat exchanger for hot water supply, and the separated liquid refrigerant flows by bypassing the second heat exchanger for hot water supply. Water heater.