Chapter 10

Question 1

Group 1 refrigerants:

A) Are easily ignited
B) Are moderately toxic
C) Are considered the safest
D) Are quite poisonous
E) None of these is correct

Answer 1

C

Question 2

Class 3 refrigerants are:

A) Non explosive
B) Moderately explosive
C) Extremely flammable
D) Moderately flammable
E) Non flammable

Answer 2

C

Question 3

As well as a low condensing pressure, a good refrigerant should have a:

A) An offensive odor
B) High evaporating temperature
C) High temperature boiling point
D) High condensing pressure
E) High latent heat of evaporation

Answer 3

E

Question 4

In a two-stage refrigeration system, the first stage is usually ____________ compressor.

A) An axial flow
B) A diffuser
C) A centrifugal
D) A reciprocating
E) A rotary

Answer 4

E

Question 5

A refrigerant may be defined as a:

A) Fluid that absorbs heat at a high pressure
B) Fluid that absorbs heat at a low temperature and pressure and gives up heat by condensing at a higher temperature and pressure
C) Medium for creating heat
D) Liquid that absorbs heat at high pressure and gives up heat at low pressure
E) Fluid that absorbs heat at a high temperature and pressure and gives up heat by condensing at a lower temperature and pressure

Answer 5

B

Question 6

In a two-stage refrigeration system, the first stage compressor is also known as ____________ compressor.

A) An extraction
B) A booster
C) A standby
D) A low volume
E) A refrigerant

Answer 6

B

Question 7

Ammonia refrigerant will:

A) Not mix with oils
B) Mix with oils when heated
C) Be added with oil for lubrication purposes
D) Mix easily with oils
E) Not mix with water

Answer 7

A

Question 8

Some reciprocating compressors on ammonia systems are protected from liquid slugs by:

A) Extra heavy valves
B) High water cut outs
C) Automatic drain traps
D) Low pressure cut outs
E) Spring loaded safety heads

Answer 8

E

Question 9

The high and low pressure sides of a compression refrigerating system are separated:

A) Between the compressor discharge and suction valves to the expansion valve
B) Between the compressor discharge and suction valves to the evaporator discharge valve
C) Between the compressor suction and the brine valve
D) From the oil separator inlet to the expansion valve
E) From the condenser to the compressor discharge valve

Answer 9

A

Question 10

The compressor best suited for a refrigeration system where the volume is large and the pressure differential is small:

A) Eccentric roller
B) Reciprocating
C) Sliding vane
D) Screw
E) Centrifugal

Answer 10

E