单选题One cause of high head pressure occurring in a refrigeration system can be （）.Ainsufficient cooling water flow to the condenserBa low refrigerant charge in the systemCthe liquid valve is open too muchDhigh evaporator superheat
单选题
One cause of high head pressure occurring in a refrigeration system can be （）.
A
insufficient cooling water flow to the condenser
B
a low refrigerant charge in the system
C
the liquid valve is open too much
D
high evaporator superheat
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