单项选择题
When adding oil to a refrigeration system, precautions must be taken to ensure that ().
A.the compressor suction pressure is not too high
B.all air is purged from the pump and charging fittings
C.the high pressure cutout switch is held open to prevent accidental starting
D.the condenser is completely shutdown first
相关考题
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单项选择题
In a refrigeration system, if the cooling water to the condenser fails, the().
A.box temperature solenoid valve will close
B.expansion valve will close
C.compressor will shutdown
D.king valve will open -
单项选择题
Accidental flooding of the engine room bilges by the bilge main is prevented by ().
A.stop-check valves installed in the bilge manifolds
B.using a positive displacement reciprocating bilge pump
C.installing eductors in all bilge rose boxes
D.installing a swing check before each bilge valve -
单项选择题
Zinc rods are installed in the refrigeration system ().
A.liquid strainer
B.liquid receiver
C.saltwater condenser
D.evaporator
