A.broken inlet valves
B.broken discharge valves
C.pulsations in the air distribution system
D.overloading of the air distribution system
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A.warping head
B.fairlead
C.wildcat
D.capstan
A.system was overcharged with refrigerant
B.high pressure switch was improperly adjusted
C.expansion valve strainers were fouled
D.suction valves were leaking slightly
A.increased pump speed
B.excessive pump discharge pressure
C.too low of a tilting box angle
D.low pump speed
A.Lube oil passing through the system
B.Moisture or foreign matter collecting at the valve seat and orifice
C.Variable spring tension caused by the changing temperature
D.Frost on the liquid line
A.an immediate crankcase explosion
B.oil contamination in the compressed air
C.a decrease in compressor capacity
D.no immediate loss of the compressed air capacity
最新試題
An increasing head pressure in a refrigeration system, without any corresponding change in the cooling water inlet temperature, would probably be caused by （）.
Heavy wear in a particular area of the inner circumference of a packing ring may be caused by （）.
Which of the following statements is correct concerning heat transfer?（）
If the thermal bulb of an expansion valve is incorrectly placed at the center of the coil instead of the end, it will （）.
When a refrigeration compressor has developed a high head pressure as a result of a refrigerant overcharge, you should （）.
Who is responsible for ensuring that someone is assigned to close the watertight doors in an emergency?（）
The amount of fluid friction or internal friction inherent in a mineral lubricating oil is reflected as a measure of its （）.
A pressure drop through the refrigerant liquid line may cause （）.
An excessive charge of refrigerant in an air-cooled refrigeration system can cause （）.
The general purpose of a heat exchanger is to （）.