RETA CIRO INDUSTRIAL REFRIGERATION
TROUBLESHOOTING FUNDAMENTALS
PRACTICE EXAM WITH ACTUAL
QUESTIONS AND VERIFIED ANSWERS,
PLUS EXPLAINED RATIONALES/EXPERT
VERIFIED FOR GUARANTEED 100% PASS
2026/LATEST UPDATE/INSTANT
DOWNLOAD PDF
1. An ammonia refrigeration system is operating with a reciprocating
compressor. The operator notices that suction pressure has
gradually fallen below its normal operating range, while discharge
pressure remains approximately normal. The compressor is
running for longer periods, and the refrigerated space is not
reaching its normal temperature. Which condition is the most
likely initial troubleshooting concern?
A. Excessive condenser water flow
B. Restricted refrigerant flow or inadequate refrigerant feed to the
evaporator
C. Excessive liquid level in the high-pressure receiver
D. Compressor discharge valve leakage
Answer: B. Restricted refrigerant flow or inadequate refrigerant
feed to the evaporator
Rationale: A low suction pressure combined with inadequate cooling
commonly indicates that the evaporator is being starved. Possible
causes include a restricted strainer, malfunctioning expansion device,
inadequate liquid supply, excessive pressure drop, or a control
problem. The compressor continues removing vapor faster than
1
,refrigerant is being properly fed to the evaporator, causing suction
pressure to fall.
2. During troubleshooting, an operator discovers that an evaporator
has a much smaller-than-normal temperature difference between
the refrigerant and the refrigerated product. The evaporator surface
is relatively warm and has little frost accumulation. Which
condition should be investigated first?
A. Excessive compressor capacity
B. Evaporator overfeeding with liquid
C. Insufficient refrigerant flow through the evaporator
D. Excessively high condensing pressure
Answer: C. Insufficient refrigerant flow through the evaporator
Rationale: An evaporator that is starved of refrigerant may have
insufficient active boiling across its surface. This reduces heat transfer
and can result in poor cooling performance. The technician should
investigate the liquid supply, expansion device, strainers, solenoid
valves, differential pressure, and associated controls before assuming
the compressor is defective.
3. An ammonia compressor has an unusually high discharge
temperature. Suction pressure is lower than normal, and the
compressor has been operating continuously. Which combination
of conditions is most likely to contribute to this problem?
A. Low superheat and excessive liquid return
B. High superheat and low suction pressure
C. High receiver level and low discharge pressure
D. Excessive condenser subcooling and high suction pressure
Answer: B. High superheat and low suction pressure
2
,Rationale: High discharge temperature can result when the
compressor operates with excessive suction superheat and/or a low
suction pressure. High superheat means the vapor entering the
compressor contains more sensible heat, while a low suction pressure
increases the compression ratio. Both conditions can significantly
increase compressor discharge temperature.
4. A reciprocating ammonia compressor begins exhibiting symptoms
consistent with liquid refrigerant entering the compressor. Which
observation would provide the strongest warning of liquid
carryover?
A. Stable suction pressure with moderate superheat
B. Low compressor discharge temperature accompanied by abnormal
mechanical noise
C. High discharge superheat and elevated discharge temperature
D. Increased condenser approach temperature only
Answer: B. Low compressor discharge temperature accompanied by
abnormal mechanical noise
Rationale: Liquid refrigerant entering a reciprocating compressor can
produce abnormally low discharge temperatures and potentially severe
mechanical damage. Liquid is essentially incompressible, so liquid
carryover can cause valve damage, broken components, oil dilution,
and other mechanical problems. Abnormal knocking or impact sounds
are particularly concerning.
5. A refrigeration system's suction pressure is higher than normal, but
the refrigerated space is still warmer than its normal setpoint. The
compressor appears to be running normally. Which condition
could explain this combination?
3
, A. Compressor capacity is insufficient relative to the load
B. The evaporator is completely starved
C. The suction line is completely blocked
D. The condenser is receiving excessive cooling water
Answer: A. Compressor capacity is insufficient relative to the load
Rationale: High suction pressure does not necessarily indicate good
refrigeration performance. If compressor capacity is insufficient for
the current load, the system may be unable to remove heat rapidly
enough, causing the suction pressure to remain elevated while space
temperature rises. Possible causes include an unusually high
refrigeration load, unloaded compressors, cylinder unloading
problems, or reduced compressor efficiency.
6. An operator notices that compressor suction pressure is
substantially higher than expected immediately after a refrigeration
load has increased. Which interpretation is most appropriate?
A. A high suction pressure always indicates an overcharged system
B. The increased evaporator load may be generating more vapor than the
compressor can immediately remove
C. The compressor must have lost all oil pressure
D. The condenser must be completely plugged
Answer: B. The increased evaporator load may be generating more
vapor than the compressor can immediately remove
Rationale: When evaporator heat load increases, more liquid
refrigerant boils and generates vapor. If compressor capacity does not
increase sufficiently to accommodate the added vapor, suction
pressure can rise. Troubleshooting should consider actual load,
compressor capacity, control response, evaporator operation, and
4
TROUBLESHOOTING FUNDAMENTALS
PRACTICE EXAM WITH ACTUAL
QUESTIONS AND VERIFIED ANSWERS,
PLUS EXPLAINED RATIONALES/EXPERT
VERIFIED FOR GUARANTEED 100% PASS
2026/LATEST UPDATE/INSTANT
DOWNLOAD PDF
1. An ammonia refrigeration system is operating with a reciprocating
compressor. The operator notices that suction pressure has
gradually fallen below its normal operating range, while discharge
pressure remains approximately normal. The compressor is
running for longer periods, and the refrigerated space is not
reaching its normal temperature. Which condition is the most
likely initial troubleshooting concern?
A. Excessive condenser water flow
B. Restricted refrigerant flow or inadequate refrigerant feed to the
evaporator
C. Excessive liquid level in the high-pressure receiver
D. Compressor discharge valve leakage
Answer: B. Restricted refrigerant flow or inadequate refrigerant
feed to the evaporator
Rationale: A low suction pressure combined with inadequate cooling
commonly indicates that the evaporator is being starved. Possible
causes include a restricted strainer, malfunctioning expansion device,
inadequate liquid supply, excessive pressure drop, or a control
problem. The compressor continues removing vapor faster than
1
,refrigerant is being properly fed to the evaporator, causing suction
pressure to fall.
2. During troubleshooting, an operator discovers that an evaporator
has a much smaller-than-normal temperature difference between
the refrigerant and the refrigerated product. The evaporator surface
is relatively warm and has little frost accumulation. Which
condition should be investigated first?
A. Excessive compressor capacity
B. Evaporator overfeeding with liquid
C. Insufficient refrigerant flow through the evaporator
D. Excessively high condensing pressure
Answer: C. Insufficient refrigerant flow through the evaporator
Rationale: An evaporator that is starved of refrigerant may have
insufficient active boiling across its surface. This reduces heat transfer
and can result in poor cooling performance. The technician should
investigate the liquid supply, expansion device, strainers, solenoid
valves, differential pressure, and associated controls before assuming
the compressor is defective.
3. An ammonia compressor has an unusually high discharge
temperature. Suction pressure is lower than normal, and the
compressor has been operating continuously. Which combination
of conditions is most likely to contribute to this problem?
A. Low superheat and excessive liquid return
B. High superheat and low suction pressure
C. High receiver level and low discharge pressure
D. Excessive condenser subcooling and high suction pressure
Answer: B. High superheat and low suction pressure
2
,Rationale: High discharge temperature can result when the
compressor operates with excessive suction superheat and/or a low
suction pressure. High superheat means the vapor entering the
compressor contains more sensible heat, while a low suction pressure
increases the compression ratio. Both conditions can significantly
increase compressor discharge temperature.
4. A reciprocating ammonia compressor begins exhibiting symptoms
consistent with liquid refrigerant entering the compressor. Which
observation would provide the strongest warning of liquid
carryover?
A. Stable suction pressure with moderate superheat
B. Low compressor discharge temperature accompanied by abnormal
mechanical noise
C. High discharge superheat and elevated discharge temperature
D. Increased condenser approach temperature only
Answer: B. Low compressor discharge temperature accompanied by
abnormal mechanical noise
Rationale: Liquid refrigerant entering a reciprocating compressor can
produce abnormally low discharge temperatures and potentially severe
mechanical damage. Liquid is essentially incompressible, so liquid
carryover can cause valve damage, broken components, oil dilution,
and other mechanical problems. Abnormal knocking or impact sounds
are particularly concerning.
5. A refrigeration system's suction pressure is higher than normal, but
the refrigerated space is still warmer than its normal setpoint. The
compressor appears to be running normally. Which condition
could explain this combination?
3
, A. Compressor capacity is insufficient relative to the load
B. The evaporator is completely starved
C. The suction line is completely blocked
D. The condenser is receiving excessive cooling water
Answer: A. Compressor capacity is insufficient relative to the load
Rationale: High suction pressure does not necessarily indicate good
refrigeration performance. If compressor capacity is insufficient for
the current load, the system may be unable to remove heat rapidly
enough, causing the suction pressure to remain elevated while space
temperature rises. Possible causes include an unusually high
refrigeration load, unloaded compressors, cylinder unloading
problems, or reduced compressor efficiency.
6. An operator notices that compressor suction pressure is
substantially higher than expected immediately after a refrigeration
load has increased. Which interpretation is most appropriate?
A. A high suction pressure always indicates an overcharged system
B. The increased evaporator load may be generating more vapor than the
compressor can immediately remove
C. The compressor must have lost all oil pressure
D. The condenser must be completely plugged
Answer: B. The increased evaporator load may be generating more
vapor than the compressor can immediately remove
Rationale: When evaporator heat load increases, more liquid
refrigerant boils and generates vapor. If compressor capacity does not
increase sufficiently to accommodate the added vapor, suction
pressure can rise. Troubleshooting should consider actual load,
compressor capacity, control response, evaporator operation, and
4
