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

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热门试题

单项选择题Refrigerant entering the compressor of a refrigeration system should be in which of the following conditions?（）

A.Sub-cooled liquid
B.Sub-cooled vapor
C.Superheated vapor
D.Liquid

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A.incorrect electrode setting
B.incorrect nozzle position
C.clogged fuel nozzle
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A.decreasing the compression ratio
B.using a special fuel having a high ignition temperature
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A.an air start cam
B.cylinder compression pressure
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单项选择题The cetane rating of diesel fuel is an indication of the （）

A.ignition quality of the fuel
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