Reversing-defrosting air source heat pump unit and reversing defrosting method

Abstract

The invention discloses a reversing-defrosting air source heat pump unit and a reversing defrosting method. The reversing-defrosting air source heat pump unit comprises a compressor, outdoor heat exchangers, a fan, an indoor heat exchanger, a gas-liquid separator, a first four-way reversing valve and a throttling mechanism. The outdoor heat exchangers are composed of the first outdoor heat exchanger and the second outdoor heat exchanger. A second four-way reversing valve is arranged in the unit to change the flowing direction of a refrigerant. Connectors of the second four-way reversing valve are connected with the throttling mechanism, the first outdoor heat exchanger, the second outdoor heat exchanger and the first four-way reversing valve correspondingly. By means of the reversing-defrosting air source heat pump unit and the reversing defrosting method, the defect that defrosting and heating cannot be conducted simultaneously according to a traditional defrosting mode of an air source heat pump unit is effectively overcome; during defrosting operation of an air source heat pump, the indoor temperature cannot be lowered, and thus comfortableness of indoor people is effectively improved; and through the second four-way reversing valve, multiple modes including refrigeration, heating, heating and reversing defrosting, and the like can be switched to operate.

Description

technical field [0001] The invention belongs to the technical field of heat pump air conditioners, in particular to a reversing defrosting air source heat pump unit and a reversing defrosting method. Background technique [0002] At present, the most common defrosting method used by air source heat pump units is reverse cycle defrosting, but this defrosting method has many disadvantages: for example, it needs to absorb heat from the room during defrosting, and the room temperature will drop by 5-6°C, which will affect the indoor environment. comfort; when switching between heating and defrosting modes, the system pressure fluctuates violently, resulting in a large mechanical impact; when defrosting, the indoor heat exchanger acts as an evaporator, and the surface temperature is as low as After heating, no hot air can be blown out for a long period of time; when the defrosting is started and terminated, the four-way reversing valve reversing causes a large airflow noise. [...

AI Technical Summary

Problems solved by technology

[0002] At present, the most common defrosting method used by air source heat pump units is reverse cycle defrosting, but this defrosting method has many disadvantages: for example, it needs to absorb heat from the room during defrosting, and the room temperature will drop by 5-6°C, which will affect the indoor environment. comfort; when switching between heating and defrosting modes, the system pressure fluctuates violently, resulting in a large mechanical impact; when defrosting, the indoor heat exchanger acts as an evaporator, and the surface temperature is as low as After heating, no hot air can be blown out for a long period of time; when starting and terminating defrosting, the four-way reversing valve reversing causes relatively large airflow noise

However, the essence of this invention is still reverse cycle defrosting, and it still cannot achieve the purpose of simultaneous defrosting and heating

Images