GCAP INDUSTRIAL AMMONIA REFRIGERATION EXAMS
SCRIPT QUESTIONS AND ANSWERS SURE A+
✔✔What is latent heat? - ✔✔Heat transfer that does not change temperature but
changes state.
✔✔Why would engineering consider insulating portions of a mechanical refrigeration
system? - ✔✔To reduce heat transfer
✔✔What are 3 acceptable techniques for NDT (Non Destructive Testing) -
✔✔Radiographic, Ultrasonic, and Infrared
✔✔Typically, insulated pipes and vessels are on what side of a mechanical refrigeration
system? - ✔✔Low side - suction
✔✔A Pressure gauge is measuring an area of 1 square inch, and there is a force of 30
pounds on the area. What is the pressure? - ✔✔[P=F/A] 30/1 =30 PSI
✔✔181 PSIG equals what pressure in PSIA? - ✔✔[PSIG to PSIA = +14.7]
181+14.7=195.7 PSIA
✔✔54 PSIA equals what pressure in PSIG? - ✔✔[PSIA to PSIG = -14.7] 54-14.7=39.3
PSIG
✔✔Changing the pressure upon a refrigerant changes? - ✔✔Boiling and condensing
temperature.
✔✔Is 10 PSIG a greater pressure than 10 PSIA? - ✔✔Yes, by 14.7 PSI
✔✔If you say a refrigerant is sub-cooled, you are saying it is at a temperature below its
SAT point and a _______________? - ✔✔Liquid only.
✔✔If you see a refrigerant is superheated, you are saying it is at a temperature above
SAT point and a ______________? - ✔✔Gas only.
✔✔If you say a refrigerant is SAT, you are saying there is _________________? -
✔✔Gas and liquid combination.
✔✔An Ammonia refrigerant line contains Ammonia at the following conditions:
● 11"Hg (-44° F)
● -20° F
What is the condition of the refrigerant? - ✔✔Superheated
, ✔✔An Ammonia refrigerant line contains the following conditions:
● 181 PSIG (95° F)
● 77°F
What is the condition of the refrigerant? - ✔✔Sub-cooled
✔✔An Ammonia refrigerant line contains the following conditions:
● 10 PSIG (-8° F)
● -8°F
What is the condition of the refrigerant? - ✔✔SAT
✔✔Where should a superheated gas exist in all refrigeration systems? - ✔✔Inlet of
compressor.
✔✔There is considered to be four major components of refrigeration system; such as
the compressor, condenser, expansion device, and evaporator. What are two other
components that are just as critical as the four steps of refrigeration? - ✔✔Piping and
refrigerant
✔✔The four basic components creates four sections of pressure and refrigerant
state(Liquid/ Gas). Where is the worst place to have a leak? - ✔✔High side liquid
✔✔The compressor controls low side boiling temperature by controlling? - ✔✔Pressure.
✔✔A compressor is considered a/an? - ✔✔Volume reducer.
✔✔A condenser converts the refrigerant from __________to___________ when it
removes heat. - ✔✔Gas to liquid
✔✔The metering or expansion valve controls? - ✔✔Flow.
✔✔To classify a metering valve as an actual expansion valve what must happen across
the valve? - ✔✔Pressure drop, Temperature drop, and Increase in velocity.
✔✔Evaporators can be coolers, freezers, blast freezers, ice machines etc., what is one
common application to them all as the refrigerant absorbs heat? - ✔✔Convert liquid to
gas by absorbing heat.
✔✔If one dropped suction pressure of a refrigerant system, what 3 things would
happen? - ✔✔Rise in Discharge/Temperature pressure, and compression ratio.
✔✔If one increase superheat on the inlet of the compressor, what would most likely
happen? - ✔✔Rise in discharge temperature
SCRIPT QUESTIONS AND ANSWERS SURE A+
✔✔What is latent heat? - ✔✔Heat transfer that does not change temperature but
changes state.
✔✔Why would engineering consider insulating portions of a mechanical refrigeration
system? - ✔✔To reduce heat transfer
✔✔What are 3 acceptable techniques for NDT (Non Destructive Testing) -
✔✔Radiographic, Ultrasonic, and Infrared
✔✔Typically, insulated pipes and vessels are on what side of a mechanical refrigeration
system? - ✔✔Low side - suction
✔✔A Pressure gauge is measuring an area of 1 square inch, and there is a force of 30
pounds on the area. What is the pressure? - ✔✔[P=F/A] 30/1 =30 PSI
✔✔181 PSIG equals what pressure in PSIA? - ✔✔[PSIG to PSIA = +14.7]
181+14.7=195.7 PSIA
✔✔54 PSIA equals what pressure in PSIG? - ✔✔[PSIA to PSIG = -14.7] 54-14.7=39.3
PSIG
✔✔Changing the pressure upon a refrigerant changes? - ✔✔Boiling and condensing
temperature.
✔✔Is 10 PSIG a greater pressure than 10 PSIA? - ✔✔Yes, by 14.7 PSI
✔✔If you say a refrigerant is sub-cooled, you are saying it is at a temperature below its
SAT point and a _______________? - ✔✔Liquid only.
✔✔If you see a refrigerant is superheated, you are saying it is at a temperature above
SAT point and a ______________? - ✔✔Gas only.
✔✔If you say a refrigerant is SAT, you are saying there is _________________? -
✔✔Gas and liquid combination.
✔✔An Ammonia refrigerant line contains Ammonia at the following conditions:
● 11"Hg (-44° F)
● -20° F
What is the condition of the refrigerant? - ✔✔Superheated
, ✔✔An Ammonia refrigerant line contains the following conditions:
● 181 PSIG (95° F)
● 77°F
What is the condition of the refrigerant? - ✔✔Sub-cooled
✔✔An Ammonia refrigerant line contains the following conditions:
● 10 PSIG (-8° F)
● -8°F
What is the condition of the refrigerant? - ✔✔SAT
✔✔Where should a superheated gas exist in all refrigeration systems? - ✔✔Inlet of
compressor.
✔✔There is considered to be four major components of refrigeration system; such as
the compressor, condenser, expansion device, and evaporator. What are two other
components that are just as critical as the four steps of refrigeration? - ✔✔Piping and
refrigerant
✔✔The four basic components creates four sections of pressure and refrigerant
state(Liquid/ Gas). Where is the worst place to have a leak? - ✔✔High side liquid
✔✔The compressor controls low side boiling temperature by controlling? - ✔✔Pressure.
✔✔A compressor is considered a/an? - ✔✔Volume reducer.
✔✔A condenser converts the refrigerant from __________to___________ when it
removes heat. - ✔✔Gas to liquid
✔✔The metering or expansion valve controls? - ✔✔Flow.
✔✔To classify a metering valve as an actual expansion valve what must happen across
the valve? - ✔✔Pressure drop, Temperature drop, and Increase in velocity.
✔✔Evaporators can be coolers, freezers, blast freezers, ice machines etc., what is one
common application to them all as the refrigerant absorbs heat? - ✔✔Convert liquid to
gas by absorbing heat.
✔✔If one dropped suction pressure of a refrigerant system, what 3 things would
happen? - ✔✔Rise in Discharge/Temperature pressure, and compression ratio.
✔✔If one increase superheat on the inlet of the compressor, what would most likely
happen? - ✔✔Rise in discharge temperature
