单项选择题
A.dirty delivery ducts B.too much refrigerant C.the fouling filters D.high temperature outside
（）is used in typical marine pattern self-contained unit...
单项选择题（）is used in typical marine pattern self-contained unit.
A.a water cooled condenser B.a slop tank C.a expansion tank D.a centrifugal pump
Which one is not the component of a typical, marine pat...
单项选择题Which one is not the component of a typical, marine pattern self-contained unit?（）
A.a centrifugal fan B.a direct expansion cooler C.a hermetic compressor D.a centrifugal pump
With ducted air conditioning systems, the modern tenden...
单项选择题With ducted air conditioning systems, the modern tendency is to use（）
A.central air conditioning system B.high velocity system C.low velocity system D.single duct system
