Refrigeration System Quiz

Which of the following is not a major component of the compression refrigeration cycle?

• Compressor

• Condenser

• Evaporator

• Suction-line drier

To throttle or regulate the flow of fluid as opposed to just starting and stopping it is called blank 1.

• pulsing

• modulating

• rationing

• mixing

The purpose of the crankcase pressure-regulating valve is to

• maintain constant pressure in the crankcase.

• maintain constant pressure in the evaporator.

• prevent a compressor from going into a vacuum.

• prevent a compressor overload condition.

The _______ valve can move in very small increments or steps to either open or close the suction line in response to the discharge air temperature of a refrigerated case.

• electronic evaporator pressure-regulating

• thermostatic expansion

• electronic expansion

• crankcase pressure-regulating

An automatic pumpdown system may be used to

• maintain a constant evaporator pressure during low-load conditions.

• raise system head pressure during low-ambient conditions.

• prevent surges of liquid refrigerant from entering the compressor (slugging) during start-up.

• prevent liquid refrigerant from becoming trapped in the receiver.

On a “one-time” or non-short-cycling pumpdown system

• a leaking solenoid valve or compressor discharge valve will cause the system to turn back on.

• only the thermostat calling again for cooling will take the refrigeration system out of pumpdown.

• the refrigerant is stored in a liquid receiver and must be manually released back into the system.

• once the system has been pumped down, it will lock out, requiring service.

Two types of relief valves are blank 1_.

• check and spring-loaded

• manual and ball

• spring-loaded and one-time

• one-time and multiuse

To prevent the head pressure from dropping to the point that the expansion valve will not feed correctly

• a pumpdown system is used.

• an evaporator pressure regulator is used.

• low-ambient controls are used.

• a high-pressure control is used.

Which of the following is not a method of low-ambient control on air-cooled equipment?

• Modulating TXV

• Fan-cycling controls

• Condenser flooding

• Fan speed control

Which of the following is used as a protection against operation with a low charge or as a temperature control for some refrigeration evaporators?

• Oil safety switch

• Thermostat

• High-pressure switch

• Low-pressure switch