loose expansion valve control bulb
low differential setting on the H-Pcutout
blown fuse in the motor circuit
faulty suction pressure regulator
第1题：
Sweating of the refrigeration system compressor crankcase is caused by_______ .
A.too much superheat
B.insufficient superheat
C.suction pressure too low
D.excessive refrigerant returning to the compressor
第2题：
insufficient condenser cooling water
excessive condenser cooling water
air in the refrigeration system
excessive refrigerant in the system
第3题：
If the refrigeration compressor crankcase is sweating, the cause may be due to
A.a shortage of refrigerant
B.the compressor running continuously
C.liquid refrigerant returning to the compressor
D.the compressor short cycling on the high pressure cutout
第4题：
increase compressor discharge pressure on demand
increase compressor operating speed as necessary
allow the motor to turn the compressor opposed only by friction
reduce the compressor frictional load when starting
第5题：
flooding back
superheating
overflowing
recycling
第6题：
If the suction pressure for an operating refrigeration compressor is below normal, the cause may be ______.
A.an excess of liquid refrigerant
B.the expansion valve overfeeding
C.a fouled compressor suction strainer
D.the compressor short cycling
第7题：
leaking discharge valve
jammed suction valve
tripped overload relay
broken discharge un-loader
第8题：
Excessive oil foaming in the crankcase of a refrigeration compressor is most likely to occur when the compressor
A.has run continuously for a long period
B.suction pressure is below normal
C.oil level is below normal
D.starts after a long idle period
第9题：
overheated compressor bearings
excess lube oil viscosity
carbon deposits on the compressor piston rings
wax crystals forming in the lubricant
第10题：
the compressor suction pressure is not too high
all air is purged from the pump and charging fittings
the high pressure cutout switch is held open to prevent accidental starting
the condenser is completely shutdown first