Method for defrosting an air conditioning system

Abstract

The invention provides a method for defrosting an air conditioning system. The air conditioning system comprises an indoor heat exchanger, throttle devices, an outdoor heat exchanger, a four-way valve, a compressor, a bypass circuit branch and a junction main circuit which are arranged on refrigerant circulation paths in a heating mode, wherein the compressor is connected with the indoor heat exchanger and the outdoor heat exchanger through the four-way valve; a heat accumulator is arranged on and connected with the compressor; the bypass circuit branch is connected between the four-way valve and the outdoor heat exchanger; and the junction main circuit is connected between the throttle devices and connected with the compressor by the heat accumulator. During defrosting, a refrigerant flows out of the compressor and passes through the four-way valve for bypassing, a part of the refrigerant enters the outdoor heat exchanger for defrosting through the bypass circuit branch, the other part of the refrigerant enters the indoor heat exchanger for heating, after heat exchange, the two parts of the refrigerant are subject to throttling, flow into the junction main circuit, enter the heat accumulator for heating, and then return to the compressor, so that the circulation is completed. The two parallel refrigerant circulation paths are formed in a defrosting state, so that the defrosting and continuous heating can be ensured at the same time.

Description

technical field [0001] The invention belongs to the technical field of air-conditioning control, and in particular relates to a defrosting method for an air-conditioning system. Background technique [0002] When the household air conditioner is heating, due to the low outdoor evaporation temperature, frosting occurs on the outdoor heat exchanger, which affects the heat exchange capacity of the outdoor heat exchanger and reduces the heating effect of the air conditioner. In order to ensure the heating capacity of the air conditioner, after the air conditioner has been running for a period of time to generate heat, it needs to be defrosted. Generally, the air conditioner adopts the reverse cycle method for defrosting, that is, by changing the flow direction of the refrigerant in the air conditioner, the refrigerant discharged from the compressor first enters the outdoor heat exchanger for defrosting, and then returns to the compressor through the indoor heat exchanger. Howev...

AI Technical Summary

Problems solved by technology

However, when the reverse cycle method is used for defrosting, because the temperature of the refrigerant in the indoor heat exchanger is very low at this time, it cannot be used for heating, and the fan of the air conditioner needs to stop running. Frost will not only affect the heating effect, but also easily cause obvious fluctuations in indoor temperature and reduce indoor comfort

[0003] In addition, when the air conditioner is heating, the compressor usually does work and generates heat. This part of the heat is often directly transferred to the outdoor air for loss, resulting in a lot of waste of heat.

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