A.yearly
B.quarterly
C.monthly
D.daily
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A.evaporator pressure decrease
B.evaporator coil over-feed
C.evaporator capacity increase
D.expansion valve diaphragm rupture
A.head capacity to improve
B.discharge to be reversed
C.efficiency to decrease
D.slippage to decrease
A.gums, acids, and varnishes
B.removed by cellulose type filters
C.neutralized by oil additives
D.not removed by absorbent filters
A.repack all valve stems
B.lubricate it prior to use
C.replace the foundation bolts
D.balance the warping heads
A.blue
B.green
C.orange
D.purple
最新試題
If the relief valve on the discharge side of a hydraulic pump lifts, the cause could be （）.
If the head pressure of a reciprocating refrigeration compressor is excessive, （）.
The general purpose of a heat exchanger is to （）.
Thermostatic expansion valves can be adjusted for （）.
Who is responsible for ensuring that someone is assigned to close the watertight doors in an emergency?（）
If the suction pressure at the refrigeration compressor is below normal, the cause can be（）.
Pitting in the suction areas of a centrifugal pump bronze impeller is usually caused by （）.
If you are given the job of adding hydraulic fluid to a mooring winch, and are not certain as to the type of fluid to use, you should （）.
Which of the listed pumps is NOT a positive displacement pump?（）
An excessive charge of refrigerant in an air-cooled refrigeration system can cause （）.