PURPOSE: For simplifying operation control, to connect a plurality of freezers to a single air conditioning load so that said freezers connected to compressors stopped independently from each other when the output of said compressors has become lower than the set value thereof.

CONSTITUTION: A temperature controlling load 1 such as an air conditioning fan coil heat accumulator is so constructed as to obtain a required value of heat for cooling or heating from the operated side heat exchangers 3A, 3B, 3C... of a plurality of heat pump units HA, HB, HC... A proper quantity to an air conditioning load 1 of said heat pump units HA, HB, HC are operated in combination and controlled by a controller 12 having heat source side heat exchangers 4A, 4B, 4C..., decompression devices 5A, 5B, 5C..., and said compressors 7A, 7B, 7C... and fed with the outputs of compressors 7A, 7B, 7C... which outputs are fed from the detectors 8A, 8B, 8C... fitted in the inflow duct for said air conditioning load 1 correspondingly to said compressors 7A, 7B, 7C...