Unit 25

By means of a dip tube

How does the receiver ensure that only 100% liquid refrigerant enters the liquid line?

True

(T/F) Oil separators work on the principle of low refrigerant and oil velocity.

Receiver and condenser

When a system pumps down, where is the refrigerant stored?

CPR

To protect the compressor during period of hot pull down, a _____ valve is used.

10

The refrigeration compressor motor can be operated at about ____% over its rated capacity without harm during this pulldown.

True

(T/F) Two-temperature operation is desirable when more than one evaporator is used with one compressor.

Fan cycling

Which of the following is a type of low ambient temperature head pressure control?

A low ambient control

Refrigeration systems are designed to operate year round. For this reason they are equipped with ____.

False

(T/F) Helical oil separators are about 58% efficient in separating oil.

Air volume control using shutters and fan cycling

Which of the following is another type of low ambient temperature head pressure control?

Ambient temperature controller

Frequently on smaller condensing units, one fan will run continuously and the other fan will be cycled on and off with a ____.

Back seated

The normal position for a suction service valve during normal operation is ____.

Hot gas from the compressor

Defrost using internal heat is accomplished using ____.

When the refrigeration system has enough reserve capacity to cool more than the load requirement

Random defrost is accomplished ____.

True

(T/F) The crankcase pressure regulator (CPR) puts a limit on the pressure that can return to the compressor.

Solenoid valves

_____ are snap-acting valves that open and close very fast with the electrical energy to the coil.

False

(T/F) A suction line accumulator is used to ensure that liquid refrigerant enters the compressor.

ORI

EPR valves are also referred to as ____ valves.

More than one evaporator is used with one compressor

Two-temperature operation of a refrigeration system is necessary when _____.