Refrigeration Exam Questions with
Reviewed Correct Answers
What kind of heat process is occurring in the evaporator? - Answer- Latent and sensible
Why is the pressure raised in the refrigeration cycle? - Answer- Raise temperature
above outside temperature
What is the maximum storage temperature for a cylinder of refrigerant? - Answer- 125 F
What is the flexible tube called that is found in a pressure gauge? - Answer- Bourbon
tube
How tight do you install refrigerant hoses on Schrader valves? - Answer- Snug, hand
tight
What position is a valve when it is back seated? - Answer- open
In what part of the refrigeration system should flash gas not occur? - Answer- Liquid line
In what part of the refrigeration system is a filter drier normally installed? - Answer-
Liquid line
Where would you install a sight glass? - Answer- Liquid line
Why is the pressure reduced at the metering device? - Answer- Drop pressure so
saturation temperature will be lower then medium being cooled
What should always be re-installed on a system after removing the gauge manifold
hoses from the system? - Answer- The cap
Specific heat of ice - Answer- .5
Specific heat of water - Answer- 1
Specific heat of steam - Answer- .48
how do you change gauge pressure to absolute - Answer- add 14.7
Absolute temperature is in what? - Answer- Kelvin and Rankin
, F to rankin formula - Answer- R= F-460
C to Kelvin formula - Answer- K= C-273
C to F formula - Answer- F=
F to C formula - Answer- C=
how many btu in a ton of refrigerant - Answer- 12000
how many microns in an inch - Answer- 25400
latent heat of ice - Answer- 144 BTU
Latent heat of steam - Answer- 970 BTU
absolute temperature is measured in? - Answer- kelvin
rankin
3 groups of compressors - Answer- hermatic
semi hermatic
open
explain open compressor - Answer- motor external to system, has to be cooled by other
means
What cools semi hermatic and hermatic compressors? - Answer- refrigerant
some need water jacket to help
5 types of compressors - Answer- scroll
rotary
screw
centrifugal
reciprocating piston
most common compressor in ac? - Answer- scroll
type of compressor that used to be most common and is still most common in
refrigeration - Answer- reciprocating piston
which compressor is not positive displacement? - Answer- centrifugal
where is 'A' coil normally found? - Answer- residential A/C
What is the actual structural design of A coil - Answer- copper tube, aluminum fin
Reviewed Correct Answers
What kind of heat process is occurring in the evaporator? - Answer- Latent and sensible
Why is the pressure raised in the refrigeration cycle? - Answer- Raise temperature
above outside temperature
What is the maximum storage temperature for a cylinder of refrigerant? - Answer- 125 F
What is the flexible tube called that is found in a pressure gauge? - Answer- Bourbon
tube
How tight do you install refrigerant hoses on Schrader valves? - Answer- Snug, hand
tight
What position is a valve when it is back seated? - Answer- open
In what part of the refrigeration system should flash gas not occur? - Answer- Liquid line
In what part of the refrigeration system is a filter drier normally installed? - Answer-
Liquid line
Where would you install a sight glass? - Answer- Liquid line
Why is the pressure reduced at the metering device? - Answer- Drop pressure so
saturation temperature will be lower then medium being cooled
What should always be re-installed on a system after removing the gauge manifold
hoses from the system? - Answer- The cap
Specific heat of ice - Answer- .5
Specific heat of water - Answer- 1
Specific heat of steam - Answer- .48
how do you change gauge pressure to absolute - Answer- add 14.7
Absolute temperature is in what? - Answer- Kelvin and Rankin
, F to rankin formula - Answer- R= F-460
C to Kelvin formula - Answer- K= C-273
C to F formula - Answer- F=
F to C formula - Answer- C=
how many btu in a ton of refrigerant - Answer- 12000
how many microns in an inch - Answer- 25400
latent heat of ice - Answer- 144 BTU
Latent heat of steam - Answer- 970 BTU
absolute temperature is measured in? - Answer- kelvin
rankin
3 groups of compressors - Answer- hermatic
semi hermatic
open
explain open compressor - Answer- motor external to system, has to be cooled by other
means
What cools semi hermatic and hermatic compressors? - Answer- refrigerant
some need water jacket to help
5 types of compressors - Answer- scroll
rotary
screw
centrifugal
reciprocating piston
most common compressor in ac? - Answer- scroll
type of compressor that used to be most common and is still most common in
refrigeration - Answer- reciprocating piston
which compressor is not positive displacement? - Answer- centrifugal
where is 'A' coil normally found? - Answer- residential A/C
What is the actual structural design of A coil - Answer- copper tube, aluminum fin
