JPH03113244A - Air-conditioning device - Google Patents

Abstract

PURPOSE:To prevent a compressor from being interrupted in its operation upon starting heating by providing a heat source side refrigerant cycle and a utilization side refrigerant cycle, and providing a control device for opening a solenoid valve provided in parallel to a heating pressure reduction device by difference pressure detector device between inlet and outlet pressures in a refrigerant carrier device. CONSTITUTION:A difference pressure detector device 14 is actuated as pressure difference between inlet pressure and outlet pressure in a refrigerant carrier device 11 becomes less than a predetermined valve owing to reduction of the amount of carried refrigerant, and hence a control device 15 opens a solenoid valve 13. Accordingly, the amount of pressure reduction is lowered to reduce the amount of exchanged heat (amount of heat absorption) in a heat source side heat exchanger 3 and further reduce the amount of exchanged heat (amount of heat dissipation) in a first auxiliary heat exchanger 8. Thus, high pressure can also be lowered. Hereby, a compressor is prevented from being interrupted even through capability of the refrigerant carrier device is deteriorated for a predetermined time upon starting of heating operation.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to a refrigerant cycle for a heating and cooling system.

Conventional technology Conventionally, the refrigerant cycle of air conditioning equipment separated into a heat source side refrigerant cycle and a user side refrigerant cycle was disclosed in Japanese Patent Application Laid-Open No. 62-2389.
It was disclosed in Japanese Patent No. 51 and was constructed as shown in Figure 2. In Fig. 2, 1 is a compressor, 2 is a four-way valve on the heat source side,
3 is a heat source side heat exchanger, 4 is a pressure reducing device for cooling, 6 is a pressure reducing device for heating, 6 is a check valve that closes the cooling pressure reducing device 4t during heating, and 7 is a pressure reducing device for heating 6 that is closed during cooling. check valve,
8 is a first auxiliary heat exchanger which is connected in an annular manner to form a heat source side refrigerant cycle IL/. A second auxiliary heat exchanger 9 is integrally formed to exchange heat with the first auxiliary heat exchanger 8. 1o is a refrigerant amount adjustment tank that adjusts the amount of refrigerant during cooling and heating. Reference numeral 11 denotes a refrigerant conveying device which has a reversible characteristic such that the outflow direction of the refrigerant is opposite during cooling and heating, and is housed in the heat source side unit a).

Reference numeral 12 denotes a heat exchanger on the user side, which is housed in the user side unit)b and connected to the heat source side unit)a through a connecting pipe Crc/.

The second auxiliary heat exchanger 9 and the refrigerant amount adjustment tank 10° refrigerant conveying device 11. Usage side heat exchanger 12 and connection piping fi
It is continuous in an annular shape and forms a user-side refrigerant cycle.

The operation of the heating and cooling system configured as described above will be explained.

During cooling operation, the refrigerant cycle shown by the solid line arrow in the figure is used.In the refrigerant cycle on the heat source side, high-temperature, high-pressure gas from the compressor 1 passes through the four-way valve 2, radiates heat in the heat exchanger 3 on the heat source side, condenses and liquefies, and is prevented from returning. It passes through the valve 6, is depressurized by the cooling expansion valve 4, is evaporated in the first auxiliary heat exchanger 8, and is circulated through the heat source side four-way valve 2 to the compressor 1. At this time, the second auxiliary heat exchanger 9 of the refrigerant cycle on the user side
The first auxiliary heat exchanger 8 exchanges heat, and the gas refrigerant in the user-side refrigerant cycle is cooled and liquefied, and is sent to the refrigerant conveyance device 11 through the refrigerant amount adjustment tank 1o. It is sent to the user-side heat exchanger 12 through the connecting pipe cf, where it is cooled, endothermically evaporated, gasified, and circulated through the connecting pipe a'k to the second auxiliary heat exchanger 9.

On the other hand, during heating operation, the refrigerant cycle is indicated by the dashed arrow in the figure, and in the heat source side refrigerant cycle, the high temperature, high pressure refrigerant from the compressor 1 is sent from the heat source side four-way valve 2 to the first auxiliary exchanger 8, where it radiates heat. It is condensed and liquefied, the pressure is reduced through the check valve 7 by the heating pressure reducing device 5, it is endothermically evaporated in the heat source side heat exchanger 3, and is circulated through the heat source side four-way valve 2 to the compressor 1. At this time, the second auxiliary heat exchanger 9 of the user-side refrigerant cycle and the first auxiliary heat exchanger 8 exchange heat, and the liquid refrigerant in the user-side refrigerant cycle is heated and gasified, passing through the connecting pipe C'. The refrigerant is sent to the user side heat exchanger 12, heated and liquefied with heat radiation, and sent to the refrigerant conveying device 11 through the connection pipe C, and circulated from the refrigerant amount adjustment tank 10 to the second auxiliary heat exchanger 9.

Problems to be Solved by the Invention However, with the above configuration, if the refrigerant conveyance device is operated at the same time as the compressor of the heat source side refrigerant cycle at the start of heating operation, part of the gas refrigerant of the user side refrigerant cycle will be transferred to the refrigerant. This will flow into the equipment and reduce the refrigerant transport capacity. Therefore, the heat exchange capacity of the second auxiliary heat exchanger decreases, the heat exchange capacity of the first auxiliary heat exchanger, that is, the heat dissipation and condensation capacity of the heat source side refrigerant cycle decreases, and the high pressure increases, causing the compressor to operate. There was a risk that it would stop.

In order to solve this problem, a method of controlling the capacity of the compressor has been considered, but this method has the drawbacks of requiring a complicated structure and increasing costs.

In view of the above-mentioned problems, the present invention provides an air-conditioning and heating system that has a simple configuration and that does not cause the compressor to stop operating even if the transport capacity of the refrigerant transport system decreases at the start of heating operation.

Means for Solving the Problems In order to solve the above problems, the air conditioning system of the present invention includes:
a heat source side refrigerant cycle, a user side refrigerant cycle, a solenoid valve provided in parallel with a heating pressure reducing device, and a differential pressure detection device that detects a differential pressure between an inlet pressure and an outlet pressure of the refrigerant transfer device;
and a control device that opens the electromagnetic valve based on the differential pressure detected by the differential pressure detection device.

According to the above-described configuration, the capacity of the heat source side refrigerant cycle decreases during the predetermined waiting time for starting the heating operation, and the heat exchange heat amount (heat radiation amount) in the first auxiliary heat exchanger decreases.
This means that the high pressure can also be lowered.

EXAMPLE Hereinafter, a heating and cooling system according to an example of the present invention will be described with reference to the drawings. FIG. 1 shows a refrigerant cycle of a heating and cooling system according to an embodiment of the present invention. In FIG. 1, 13 is a solenoid valve installed in parallel with the heating pressure reducing device 5, 14 is a differential pressure detection device for detecting the differential pressure between the inlet pressure and the outlet pressure of the refrigerant conveying device 11, and 15 is a differential pressure detector. This is a control device that opens the electromagnetic valve based on the differential pressure detected by the device 14. The rest is the same as the conventional example, and the same reference numerals are used here to omit the explanation. The operation of this refrigerant cycle is also the same as that of the conventional example, and although the details are omitted, the differential pressure between the inlet pressure and the outlet pressure of the refrigerant conveying device 11 during heating operation becomes smaller by a predetermined amount due to a decrease in the amount of refrigerant conveyed. (for example, 0.5KP/c++!), the differential pressure detection device 14 is activated, and the control device 15 controls the solenoid valve 1.
I am trying to open 3. Therefore, the amount of pressure reduction decreases, the heat exchanged heat amount (heat absorption amount) of the heat source side heat exchanger 3 decreases, and the heat exchanged heat amount (heat radiation amount) in the first auxiliary heat exchanger 8 decreases, so the high pressure also decreases. can do.

As described above, according to this embodiment, the differential pressure between the inlet pressure and outlet pressure of the heat source side refrigerant cycle, the user side refrigerant cycle, the electromagnetic valve provided in parallel with the heating pressure reducing device, and the refrigerant transfer device 11 is controlled. Since it is equipped with a differential pressure detection device that detects the pressure difference and a control device that opens the solenoid valve based on the differential pressure detected by the differential pressure detection device, the ability of the refrigerant conveying device decreases during the predetermined waiting time to start the heating operation. Also, since the heat exchange heat amount (heat absorption amount) of the heat source side heat exchanger decreases and the heat exchange heat amount (heat release amount) in the first auxiliary heat exchanger decreases, the high pressure can also be lowered. Therefore, there is no possibility that the compressor will stop due to a rise in high pressure when starting the heating operation.

Effects of the Invention As described above, the present invention detects the differential pressure between the inlet pressure and outlet pressure of the heat source side refrigerant cycle, the user side refrigerant cycle, the solenoid valve provided in parallel with the heating pressure reducing device, and the refrigerant conveyance device. and a control device that opens the solenoid valve based on the differential pressure detected by the differential pressure detection device,
During the predetermined time for starting heating operation, the heat exchange heat amount (heat absorption amount) of the heat source side heat exchanger decreases, and the heat exchange heat amount (heat release amount) of the first auxiliary heat exchanger decreases, so the high pressure is also low. can do. Therefore, even if the transport capacity of the refrigerant transport device decreases during startup, there is no risk that the high pressure in the heat source side refrigerant cycle will rise and the compressor will stop, and stable operation can be achieved.

[Brief explanation of drawings]

FIG. 1 is a refrigerant cycle diagram of a heating and cooling system according to an embodiment of the present invention, and FIG. 2 is a diagram of a refrigerant cycle of a conventional heating and cooling system. 3... Heat source side heat exchanger, 3a... Heat source side blower, 8... First auxiliary heat exchanger, 9...
... Second auxiliary heat exchanger, 11 ... Refrigerant conveyance device, 12 ... User side heat exchanger, 13 ...
・Solenoid valve, 14...Differential pressure detection device, 16...
···Control device.

Claims (1)

[Claims] A heat source side refrigerant cycle formed by connecting a compressor, a four-way valve, a heat source side heat exchanger, a pressure reducing device for cooling, a pressure reducing device for heating, and a first auxiliary heat exchanger in an annular manner, and integrated with this first auxiliary heat exchanger. a user-side refrigerant cycle in which a second auxiliary heat exchanger for heat exchange, a refrigerant transport device, and a user-side heat exchanger are connected in an annular manner; a solenoid valve provided in parallel with the heating pressure reducing device; A heating and cooling device comprising: a differential pressure detection device that detects a differential pressure between an inlet pressure and an outlet pressure of the device; and a control device that opens the electromagnetic valve based on the differential pressure detected by the differential pressure detection device.