单选题If the head pressure is too high,（）Athe relief valve should open before the high-pressure cutoutBthe relief valve should open and let excess refrigerant go to receiverCthe high-pressure cutout switch should operate before the relief valve opensDclose in on the suction valve
单选题
If the head pressure is too high,（）
A
the relief valve should open before the high-pressure cutout
B
the relief valve should open and let excess refrigerant go to receiver
C
the high-pressure cutout switch should operate before the relief valve opens
D
close in on the suction valve
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