单选题When you adjust a thermostatic expansion valve, （）.Arefrigerant must be bled off the sensing line before adjustments are madeBall refrigerant must be pumped into the receiver before adjustments are madeCtime must be allowed for conditions to stabilize in the evaporator before further adjustments are madeDall refrigerant must be routed through the dehydrator while changing the superheat setting
单选题
When you adjust a thermostatic expansion valve, （）.
A
refrigerant must be bled off the sensing line before adjustments are made
B
all refrigerant must be pumped into the receiver before adjustments are made
C
time must be allowed for conditions to stabilize in the evaporator before further adjustments are made
D
all refrigerant must be routed through the dehydrator while changing the superheat setting
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