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
A.eliminate hot air from the condenser
B.maintain steady pressure in a system
C.heat, or cool one fluid by means of another fluid
D.reduce the engine room temperature in tropical climates
A.Cross
B.Parallel
C.Counter
D.Circular
A.remain constant along the tubes length
B.be greatest in a single pass counter flow heat exchanger
C.remain constant throughout the heat exchanger
D.vary from section to section through out the heat exchanger
A.a low load on the unit
B.a clogged pump suction strainer
C.a blockage in the line between the pump and hydraulic motor
D.the hydraulic motor turning too fast
A.cause of salt contamination
B.location of salt water contamination
C.chemical makeup of feed-water
D.level of alkalinity in condensate
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A grease gun is generally used to lubricate a ().
An internal bypass is provided on some hydraulic system suction strainers to help reduce the possibility of ().
If the thermal bulb of an expansion valve is incorrectly placed at the center of the coil instead of the end, it will ().
The rate of heat transfer between the hot and cold fluids passing through a shell-and-tube type heat exchanger will ().
A gradual decrease in the discharge pressure of an operating hydraulic pump can be caused by ().
The general purpose of a heat exchanger is to ().
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?()
The usual symptoms of cavitation in a centrifugal pump is ().
Low compressor head pressure in a refrigeration system can be caused by().