单项选择题
A.hydraulic fluid contamination B.excessive fluid friction C.turbulent fluid flow D.fluid pressure surges
Air compressor receivers should be “blown down” at leas...
单项选择题Air compressor receivers should be “blown down” at least （）.
A.yearly B.quarterly C.monthly D.daily
A thermostatic expansion valve is properly controlling ...
单项选择题A thermostatic expansion valve is properly controlling evaporator superheatAdjusting this valve to lower the superheat will result in a/an （）.
A.evaporator pressure decrease B.evaporator coil over-feed C.evaporator capacity increase D.expansion valve diaphragm rupture
It is possible to mount a double suction centrifugal pu...
单项选择题It is possible to mount a double suction centrifugal pump impeller with the vanes facing in the wrong directionThis would cause the pump （）.
A.head capacity to improve B.discharge to be reversed C.efficiency to decrease D.slippage to decrease
