A.dead band action
B.neutral zone action
C.range
D.on-off action
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A.cavitation
B.electrolysis
C.abrasion
D.corrosion
A.the relief valve should open before the high pressure cutout
B.the relief valve should open and allow the excess refrigerant to flow to the receiver
C.the high pressure cutout switch should operate before the relief valve opens
D.you should close in on the suction valve
A.cause of salt contamination
B.location of salt water contamination
C.chemical makeup of feed-water
D.level of alkalinity in condensate
A.restriction in refrigerant piping
B.air and non-condensable gases in the condenser
C.water in the refrigerant
D.flooding back of liquid refrigerant from the evaporator
A.A shortage of liquid refrigerant
B.Excessive frost on the evaporator
C.Excessive condenser cooling water
D.Insufficient condenser cooling water flow
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If the head pressure of a reciprocating refrigeration compressor is excessive, ().
When the steering gear is in operation, you should ().
The temperature differential occurring between the inlet temperature of the fluid to be cooled and the outlet temperature of the cooling medium in a shell-and-tube heat exchanger is greatest in which of the flow designs listed?()
If the relief valve on the discharge side of a hydraulic pump lifts, the cause could be ().
The major source of chemical contaminants in hydraulic fluid is ().
A salinity indicator is used to determine the ().
Which of the listed pumps is NOT a positive displacement pump?()
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 ().
An increasing head pressure in a refrigeration system, without any corresponding change in the cooling water inlet temperature, would probably be caused by ().
The usual symptoms of cavitation in a centrifugal pump is ().