Refrigeration Fundamentals

Question 1

In a refrigeration system heat is rejected by

Answer 1

latent heat of condensation in the condenser

Question 2

In a refrigeration system were does the refrigerant change from a lowpressure superheated vapor to a high-pressure superheated vapor?

Answer 2

compressor

Question 3

The main function of an expansion device is to?

Answer 3

meter the refrigerant

Question 4

The main function of a receiver is to

Answer 4

store excess refrigerant

Question 5

How does a technician determine whether or not there is liquid refrigerant leaving the evaporator?

Answer 5

calculates what the evaporator superheat is

Question 6

Which of the following is NOT TRUE about refrigerant as it enters the condenser?

Answer 6

it is subcooled

Question 7

Any additional heat added to the refrigerant after its 100% saturated vapor condition is called?

Answer 7

superheat

Question 8

Most of the heat absorbed in the low side of a refrigeration system is.

Answer 8

latent heat

Question 9

If a technician subtracted liquid line temperature from high side condensing temperature he would

Answer 9

subcooling

Question 10

An azeotropic refrigerant would be defined as.

Answer 10

a mixture of two or more refrigerants that have the same boiling point and act as one

Question 11

When a zeotropic refrigerant blend changes phase the refrigerants in the blend have different boiling points which can cause the refrigerant to

Answer 11

fractionate

Question 12

A refrigerant that is not miscible with mineral oil is

Answer 12

R-404A

Question 13

Which lubricant is most commonly used with HFC-134a refrigerant?

Answer 13

polyolester

Question 14

Polyol Ester oils are?

Answer 14

hygroscopic

Question 15

Refrigerant tanks must always be stored in an area where the temperature will not exceed

Answer 15

125º

Question 16

When transferring refrigerants from a cylinder to a working system or any other container, the technician should always wear

Answer 16

goggles with side shields and gloves

Question 17

When entering a mechanical room where a refrigerant leak is suspected the technician should?

Answer 17

use the appropriate breathing apparatus until the area has been cleared of fumes

Question 18

Which of the following gasses is non flammable and would be preferred when leak testing a system?

Answer 18

CO² & nitrogen

Question 19

Refrigerant cylinders that are labeled “Disposable”

Answer 19

by law cannot be refilled &

are color-coded for easy identification

Question 20

A refrigerant cylinder that has been DOT approved for refilling must

Answer 20

never be filled over 80% capacity

Question 21

When calculating how much refrigerant can be placed into a rechargeable cylinder, one must always take into account cylinder weight known as the

Answer 21

tare lbs

Question 22

All refrigerants have flammability and the toxicity classifications. Where could a technician best find those ratings?

Answer 22

the MSDS