To provide a refrigerant channel switching unit for a cooler/heater/air conditioner which can be assembled easily using a small number of parts having simple structure.

The refrigerant channel switching unit for a cooler/heater/air conditioner comprises a main valve body 100 having a working chamber 110 and a direction switching chamber 120, a member 200 disposed rotatably in the forward and reverse directions in the direction switching chamber 120 of the main valve body 100 in order to switch the refrigerant channel of the direction switching chamber 120 selectively, and a pilot valve for rotary operating the channel switching member 200 using high pressure refrigerant delivered from a compressor 1 and the low suction pressure.