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
A.The density of the air entering the compressor
B.The temperature of the air entering the compressor
C.The designed rotating speed of the compressor
D.A leaking head gasket
A.Differential
B.Trunk
C.Barrel
D.Valve-in-head
A.return to a neutral position
B.flood the evaporator
C.open
D.close
A.control air system
B.forced draft air system
C.supply air system
D.ships service air system
A.dehydrated
B.purged
C.plugged
D.evacuated
最新试题
If the head pressure of a reciprocating refrigeration compressor is excessive, （）.
Which of the following problems could cause the high pressure cutout switch to shut down the compressor in a refrigeration system?（）
Low compressor head pressure in a refrigeration system can be caused by（）.
The rate of heat transfer between the hot and cold fluids passing through a shell-and-tube type heat exchanger will （）.
An excessive charge of refrigerant in an air-cooled refrigeration system can cause （）.
A grease gun is generally used to lubricate a （）.
If the suction pressure at the refrigeration compressor is below normal, the cause can be（）.
Thermostatic expansion valves can be adjusted for （）.
An increasing head pressure in a refrigeration system, without any corresponding change in the cooling water inlet temperature, would probably be caused by （）.
The control mode in which the final control element is moved from one of two flexed positions to the other is known as （）.