Commercial Refrigeration Final
Exam Questions From Quizzes
with 100% Correct Answers
___ are snap-acting valves that open and close very fast when the electrical energy
is applied to the coil. - ANSWER - Solenoid valves
A suction line accumulator is used to ensure that liquid refrigerant enters the
compressor. - ANSWER - False
Defrost using internal heat is accomplished using ____. - ANSWER - hot gas from the
compressor
Helical oil separators are about 58% efficient in separating oil. - ANSWER - False
How does the receiver ensure that only 100% liquid refrigerant enters the liquid
line? - ANSWER - By means of a dip tube.
Frequently on smaller condensing units, one fan will run continuously and the other
fan will be cycled on and off with a(n) ____. - ANSWER - ambient temperature
controller
Oil separators work on the principle of low refrigerant and oil velocity. - ANSWER -
True
Random defrost is accomplished ____. - ANSWER - when the refrigeration system
has enough reserve capacity to cool more than the load requirement
Refrigeration systems are designed to operate year round. For this reason they are
equipped with ____. - ANSWER - a low-ambient control
, The crankcase pressure regulator (CPR) puts a limit on the pressure that can return
to the compressor. - ANSWER - True
Which of the following is a type of low-ambient temperature head pressure control?
- ANSWER - Fan cycling.
Package ice machines store their own ice at ____ºF in a bin below the ice maker. -
ANSWER - 32
Most package ice makers are ____-cooled. - ANSWER - air
The EPR valve is installed in the suction line at the evaporator outlet and it ____. -
ANSWER - -modulates the refrigerant vapor to the compressor
-prevents the boiling point in the evaporator from dropping below a pre-set point
-when used with a TX valve the system has the characteristics of maintaining a
constant superheat and keeping the pressure from going too low
-All of the above.
The normal position for a suction service valve during normal operation is ____. -
ANSWER - -back-seated
-front seated
-midseated
-Any of the three.
The refrigeration compressor motor can be operated at about ____% over its rated
capacity without harm during the pulldown. - ANSWER - 10
To protect a refrigeration compressor when refrigerant loss occurs, a(n)
____________________ control is used. - ANSWER - low pressure
To protect the compressor during periods of hot pull down, a(n) ____ valve is used. -
ANSWER - CPR (crankcase pressure regulator)
Exam Questions From Quizzes
with 100% Correct Answers
___ are snap-acting valves that open and close very fast when the electrical energy
is applied to the coil. - ANSWER - Solenoid valves
A suction line accumulator is used to ensure that liquid refrigerant enters the
compressor. - ANSWER - False
Defrost using internal heat is accomplished using ____. - ANSWER - hot gas from the
compressor
Helical oil separators are about 58% efficient in separating oil. - ANSWER - False
How does the receiver ensure that only 100% liquid refrigerant enters the liquid
line? - ANSWER - By means of a dip tube.
Frequently on smaller condensing units, one fan will run continuously and the other
fan will be cycled on and off with a(n) ____. - ANSWER - ambient temperature
controller
Oil separators work on the principle of low refrigerant and oil velocity. - ANSWER -
True
Random defrost is accomplished ____. - ANSWER - when the refrigeration system
has enough reserve capacity to cool more than the load requirement
Refrigeration systems are designed to operate year round. For this reason they are
equipped with ____. - ANSWER - a low-ambient control
, The crankcase pressure regulator (CPR) puts a limit on the pressure that can return
to the compressor. - ANSWER - True
Which of the following is a type of low-ambient temperature head pressure control?
- ANSWER - Fan cycling.
Package ice machines store their own ice at ____ºF in a bin below the ice maker. -
ANSWER - 32
Most package ice makers are ____-cooled. - ANSWER - air
The EPR valve is installed in the suction line at the evaporator outlet and it ____. -
ANSWER - -modulates the refrigerant vapor to the compressor
-prevents the boiling point in the evaporator from dropping below a pre-set point
-when used with a TX valve the system has the characteristics of maintaining a
constant superheat and keeping the pressure from going too low
-All of the above.
The normal position for a suction service valve during normal operation is ____. -
ANSWER - -back-seated
-front seated
-midseated
-Any of the three.
The refrigeration compressor motor can be operated at about ____% over its rated
capacity without harm during the pulldown. - ANSWER - 10
To protect a refrigeration compressor when refrigerant loss occurs, a(n)
____________________ control is used. - ANSWER - low pressure
To protect the compressor during periods of hot pull down, a(n) ____ valve is used. -
ANSWER - CPR (crankcase pressure regulator)
