A.closed, and no leakage permitted across the shaft packing
B.closed, and only slight leakage permitted across the shaft packing
C.open, and no leakage permitted across the shaft packing
D.open, and only slight leakage permitted across the shaft packing
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A.freezing point
B.floc point
C.condensing temperature
D.compression temperature
A.the circuit breaker
B.for leaks in the suction piping
C.relief valve is not properly seated
D.the suction strainer
A.increase the refrigerating effect, by decreasing the amount of flash gas
B.allow the refrigerant to enter the throttling device in a saturated condition
C.increase the refrigerating effect by increasing the amount of flash gas
D.minimize the temperature drop of the liquid as it passes through the solenoid valve to the outlet side
A.maintain adequate coil back pressure
B.prohibit flashing in the liquid line
C.reduce refrigerant volume in the system
D.reduce compressor discharge line loading
A.maintaining a steadier speed
B.delivering liquids over greater distances
C.operating for longer periods of time
D.producing a smoother discharge flow
最新試題
The usual symptoms of cavitation in a centrifugal pump is ().
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?()
Which of the following statements is correct concerning heat transfer?()
The amount of fluid friction or internal friction inherent in a mineral lubricating oil is reflected as a measure of its ().
Who is responsible for ensuring that someone is assigned to close the watertight doors in an emergency?()
Which of the following problems could cause the high pressure cutout switch to shut down the compressor in a refrigeration system?()
Thermostatic expansion valves can be adjusted for ().
A pressure drop through the refrigerant liquid line may cause ().
Which of the problems listed would came the discharge temperature of an R-12 refrigeration compressor to increase?()
A gradual decrease in the discharge pressure of an operating hydraulic pump can be caused by ().