A.a high suction head
B.rotating rings
C.badly worn bearings
D.a loose stuffing box gland
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A.solenoid valve to seize
B.compressor to hunt
C.formation of flash gas in the liquid line
D.expansion valve to freeze open
A.insufficient condenser cooling water
B.excessive condenser cooling water
C.air in the refrigeration system
D.excessive refrigerant in the system
A.Thermal expansion valve frozen open
B.Suction gas heat exchanger bypassed
C.Condenser clogged or fouled
D.High pressure cutout switch inoperative
A.noise and vibration
B.an increase in discharge pressure
C.an increase in suction pressure
D.lifting of the relief valve
A.insufficient cooling water flow to the condenser
B.a low refrigerant charge in the system
C.the liquid valve is open too much
D.high evaporator superheat
最新試題
The amount of fluid friction or internal friction inherent in a mineral lubricating oil is reflected as a measure of its （）.
If the head pressure of a reciprocating refrigeration compressor is excessive, （）.
Which of the following statements is correct concerning heat transfer?（）
Which of the problems listed would came the discharge temperature of an R-12 refrigeration compressor to increase?（）
If the thermal bulb of an expansion valve is incorrectly placed at the center of the coil instead of the end, it will （）.
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 （）.
One cause of high head pressure occurring in a refrigeration system can be （）.
The rate of heat transfer between the hot and cold fluids passing through a shell-and-tube type heat exchanger will （）.
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?（）
Thermostatic expansion valves can be adjusted for （）.