单项选择题
A.Condenser leakage B.A shortage of liquid refrigerant C.Excessive frost on the evaporator D.Not enough condenser cooling water
Insufficient refrigerant in a refrigeration plant may r...
单项选择题Insufficient refrigerant in a refrigeration plant may result in （）.
A.high discharge pressure B.frosting of the crankcase C.high temperature of the overboard water D.low suction pressure of compressor
Air that may enter a refrigeration plant tends to colle...
单项选择题Air that may enter a refrigeration plant tends to collect in the （）.
A.upper part of the receiver B.upper part of the condenser C.down stream end of the cooling coil D.outlet end of the condenser
Moisture should be kept out of an R-12 system because i...
单项选择题Moisture should be kept out of an R-12 system because it tends to cause （）.
A.icing of the automatic controls B.embrittlement of some parts of the automatic controls C.sludge in the lubricating oil D.all of the above
