Heat storage type air conditioner, and defrosting method

摘要

A heat storage type air conditioner which is free from a difficulty that, when a general cooling and heating circuit and a cold radiating and heat radiating circuit are operated separately or simultaneously, the quantities of refrigerant in those circuits become smaller or larger than required, so that its compressor is damaged or the cooling or heating capacity is lowered. When, in a heat storage type air conditioner, first and second bypass circuits 22 and 23 are closed, a general cooling and heating circuit 18 driven by a compressor 1 and a cold radiating and heat radiating circuit 21 driven by a refrigerant gas pump 13 are made independent of each other, so that a cooling operation or a heating operation is carried out with the aid of a first use-side heat exchanger 4a and a second use-side heat exchanger 4b. Therefore, in the air conditioner, the refrigerant or refrigerating machine oil will never concentrate in any one of the two circuits. In a cold storing operation or a heat storing operation for a heat storage tank 8, the two bypass circuits 22 and 23 are opened, so that the general cooling and heating circuit 18 is communicated with the cold radiating and heat radiating circuit 21. As a result, the refrigerant is led from the general cooling and heating circuit into the heat storage tank 8 to store cold or heat in the heat storing medium 7 therein.