CFESA REFRIGERATION EXAMINATION
SCRIPT 2026 COMPLETE QUESTIONS
WITH FULL SOLUTIONS
◉ Describe the basic construction of a harmonic compressor
Answer: Motor and pump assembly, sealed inside a welded canister
with only access tubes and electrical connections
◉ What is meant by volumetric efficiency
Answer: The amount of refrigeration actually pumped in every
stroke cycle of the piston compared to the actual volume of the
cylinder
◉ What is heat of compression
Answer: Amount of heat generated when the piston compresses the
low pressure refrigerant vapor into high-pressure vapor
◉ What is the maximum condensing temperature on a compressor?
Answer: 275F
◉ At what temperature will oil carbonize on the head and valve
plate on a compressor?
,Answer: 350F
◉ How does maximum condensing temperature relate to oil
carbonation?
Answer: At 2:75° condensing temperature the temperature on the
head of the compressor is about 350 the carbonizing point of oil
◉ What does a suction valve compressor look like?
Answer: Send piece of shiny spring steel
◉ How do you check the suction valves on a compressor?
Answer: Front seat, the suction service valve and make sure the
compressor pumps down to at least 15+ HG
◉ No suction valve damage on compressors due to what
Answer: Liquid sludge in the compressor
◉ Where are the important traits of refrigerant oil?
Answer: Low poor point low wax buildup, good insulating qualities
high temp carbon point
◉ What type of oil lubrication system is used on compressors under
5 hp
, Answer: Splash system
◉ What type of oil lubrication system is used on compressors over 5
hp
Answer: Oil pump
◉ How are compressors cooled
Answer: Suction vapor entering the compressor air over the
compressor from the condenser fan
◉ What does the term liquid sludging referred to?
Answer: Liquid refrigerant or oil entering the suction port of the
compressor
◉ What type of refrigerant system can be used split phase
compressors
Answer: Cap tube system
◉ What is the starting torque of a capacitor start compress?
Answer: Very high
◉ How is the coil of a potential relay wired into the circuit?
Answer: In parallel with the start whining or from C to S
SCRIPT 2026 COMPLETE QUESTIONS
WITH FULL SOLUTIONS
◉ Describe the basic construction of a harmonic compressor
Answer: Motor and pump assembly, sealed inside a welded canister
with only access tubes and electrical connections
◉ What is meant by volumetric efficiency
Answer: The amount of refrigeration actually pumped in every
stroke cycle of the piston compared to the actual volume of the
cylinder
◉ What is heat of compression
Answer: Amount of heat generated when the piston compresses the
low pressure refrigerant vapor into high-pressure vapor
◉ What is the maximum condensing temperature on a compressor?
Answer: 275F
◉ At what temperature will oil carbonize on the head and valve
plate on a compressor?
,Answer: 350F
◉ How does maximum condensing temperature relate to oil
carbonation?
Answer: At 2:75° condensing temperature the temperature on the
head of the compressor is about 350 the carbonizing point of oil
◉ What does a suction valve compressor look like?
Answer: Send piece of shiny spring steel
◉ How do you check the suction valves on a compressor?
Answer: Front seat, the suction service valve and make sure the
compressor pumps down to at least 15+ HG
◉ No suction valve damage on compressors due to what
Answer: Liquid sludge in the compressor
◉ Where are the important traits of refrigerant oil?
Answer: Low poor point low wax buildup, good insulating qualities
high temp carbon point
◉ What type of oil lubrication system is used on compressors under
5 hp
, Answer: Splash system
◉ What type of oil lubrication system is used on compressors over 5
hp
Answer: Oil pump
◉ How are compressors cooled
Answer: Suction vapor entering the compressor air over the
compressor from the condenser fan
◉ What does the term liquid sludging referred to?
Answer: Liquid refrigerant or oil entering the suction port of the
compressor
◉ What type of refrigerant system can be used split phase
compressors
Answer: Cap tube system
◉ What is the starting torque of a capacitor start compress?
Answer: Very high
◉ How is the coil of a potential relay wired into the circuit?
Answer: In parallel with the start whining or from C to S
