单项选择题
A.Height of the machine B.Temperature of the liquid seal C.Gravity disc D.Bowl diameter
The compressor in an air-cooled condensing refrigeratio...
单项选择题The compressor in an air-cooled condensing refrigeration system is short cycling on the high pressure cutout switch（）
A.system is overcharged with refrigerant B.system is low on refrigerant C.discharge valves are leaking excessively D.discharge valves are leaking slightly
A cargo hold has been determined to have a relative hum...
单项选择题A cargo hold has been determined to have a relative humidity of 80% and a dry bulb temperature of 80 ℃ and a dry bulb temperature of 85℃.When the hold is sealed and the dry bulb temperature decreases, the relative humidity in the space will （）
A.decrease B.increase C.decrease to zero D.remain unchanged
A purge recovery system is used in a centrifugal air co...
单项选择题A purge recovery system is used in a centrifugal air conditioning or refrigeration system to （）
A.purge lube oil from the liquid refrigerant B.recover water purged from the system C.separate foul gases from the receiver D.purge non-condensable gases without losing refrigerant
