Air-conditioning apparatus

摘要

The air-conditioning apparatus includes compressors (13A) and (13B) having an oil equalizing pipe (45), an accumulator (29), feedback piping (43A) and (43B) that supply liquid refrigerant in the accumulator (29) to the suction side of the compressors (13A) and (13B), and a controller (51) having an oil-equalizing control mode (53) in which the amounts of lubricating oil stored individually in the compressors (13A) and (13B) are kept at or above a certain level. The oil-equalizing control mode (53) includes a feedback step of setting the rotation speeds of the compressors (13A) and (13B) to a working rotation speed and supplying the liquid refrigerant from the accumulator (29) to the compressors (13A) and (13B), and an oil equalizing step of increasing or decreasing the rotation speeds of the compressors (13A) and (13B) from an operating rotation speed by a rotation speed difference so that the rotation speeds differ from each other. The feedback work amount of the feedback step is changed in accordance with the dilution level of the lubricating oil in the liquid refrigerant in the accumulator (29), and the oil-equalizing work amount of the oil equalizing step is changed in accordance with the dilution level of the lubricating oil in the compressors.