REFRIGERATION AIR CONDITIONING EXAM LATEST VERSION -
2025/2026- 100+ QUESTIONS AND VERIFIED ANSWERS ALL
THE BEST
10. In an air conditioning system, what is the name of the chamber where the
duct-work originates?
plenum chamber
11. What is the wet bulb temperature of air if the dry bulb temperature of the air
is 90 degrees and the relative humidity is 65%? Illustration GS-RA-22
80 degrees F
12. In general, the thermal bulb for a thermal expansion valve used in a
reciprocating air conditioning system is usually charged with what substance?
the same refrigerant as the system
3. When the relief valve opens on a refrigeration compressor discharge line, it
discharges high-pressure refrigerant vapor to what location?
suction side of the compressor
4. Which of the lettered components shown in the illustration indicates the high-
pressure cutout? Illustration GS-RA-12
X
5. The rupture disc on a low-pressure centrifugal refrigeration unit is used as an
overpressure protection device and is set to relieve at 15 psig and is most likely to
lift when the compressor is idle. Where is the rupture disc located?
on top of chiller evaporator shell
1
,1. When repairing a refrigeration system, a swaging tool set would be used to
carry out which of the following operations?
Swaging tools can be used to expand an end of one tube to fit onto a tube of the
same original outside diameter.
2. In a refrigeration system that is not protected by a water failure switch, if the
cooling water to the condenser fails, what will be the result for protective
purposes?
the compressor will shut down by the action of the high-pressure cutout switch
6. During the initial cooling down of a box temperature in a refrigeration system,
which of the devices listed is used to prevent excessive gas pressure at the
compressor suction for the purpose of prevention of overloading of the
compressor driver?
Crankcase pressure regulator
7. A reheater in an air conditioning system performs what function?
restores the conditioned air temperature to a comfortable level
8. What is one benefit of maintenance of proper air circulation in an air
conditioned cargo space?
reduced slime and mold
9. In a two stage centrifugal air conditioning system, the liquid refrigerant passes
through the condenser directly to what component?
economizer
13. Heat is removed from the refrigerant circulating through the refrigeration
system, shown in the illustration, by which component? Illustration GS-RA-12
B
2
,14. Sea water or low temperature central fresh water is typically provided to a
ship's stores refrigeration plant for what purpose?
condense the refrigerant gas
15. Zinc plates commonly found in refrigeration systems and used as sacrificial
anodes are located where?
salt water side of the condenser
16. Vapor bubbles present in the liquid upon arrival to the thermal expansion
valve in a refrigeration system may cause erosion of the expansion valve's needle
and seat. This, in turn, could cause what condition?
TXV hunting
17. Moisture entering a typical refrigeration system will most likely produce what
effect?
freeze in the expansion valve
18. A small obstruction at the thermostatic expansion valve inlet will result in
which of the following conditions?
Lower than normal suction pressure.
19. An obstructed expansion valve may be indicated by an incompletely cooled
evaporator and what other symptom?
frosting at the evaporator inlet
20. Which of the following conditions will occur if the power element of the
thermostatic expansion valve shown in the illustration loses its charge? Illustration
GS RA-07
The valve will fail closed, providing no cooling capacity.
21. If the needle and seat assembly is excessively eroded, the valve cage assembly
can be replaced. In replacing the original valve cage assembly rated at 1/2 tons,
what would be the result if the replacement valve cage was oversized at 5 tons?
Illustration GS-RA-07
3
, The expansion valve would hunt excessively, alternately starving and overfeeding
the evaporator coil.
22. If the superheat value of the thermostatic expansion valve is adjusted too
high, what would be the result?
the suction line of the compressor will be abnormally warm
23. If the superheat setting of a thermostatic expansion valve is set too low, what
would be the result, assuming that the system has a single evaporator?
the suction line will be abnormally cold and liquid may flood back to the
compressor
24. Which of the illustrated valves is used to gain access to a hermetic system and
features a Schrader core valve which is unseated by the core depressor of hose
fitting when attached? Illustration GS-RA-69
D
25. How should small appliances with less than three pounds of refrigerant be
charged with refrigerant?
vapor charged
26. Before charging a refrigeration unit, unless quick disconnect fittings are used,
the refrigerant charging hoses should be prepared in what way?
they should be purged with refrigerant
27. Which of the illustrated devices would be the LEAST accurate for the purposes
of weighing-in a refrigerant charge? Illustration GS-RA-45
C
28. Concerning the charging of refrigerant into a vapor compression refrigerating
system, which of the following is true?
when charging as a liquid it should be to the high side only
4
2025/2026- 100+ QUESTIONS AND VERIFIED ANSWERS ALL
THE BEST
10. In an air conditioning system, what is the name of the chamber where the
duct-work originates?
plenum chamber
11. What is the wet bulb temperature of air if the dry bulb temperature of the air
is 90 degrees and the relative humidity is 65%? Illustration GS-RA-22
80 degrees F
12. In general, the thermal bulb for a thermal expansion valve used in a
reciprocating air conditioning system is usually charged with what substance?
the same refrigerant as the system
3. When the relief valve opens on a refrigeration compressor discharge line, it
discharges high-pressure refrigerant vapor to what location?
suction side of the compressor
4. Which of the lettered components shown in the illustration indicates the high-
pressure cutout? Illustration GS-RA-12
X
5. The rupture disc on a low-pressure centrifugal refrigeration unit is used as an
overpressure protection device and is set to relieve at 15 psig and is most likely to
lift when the compressor is idle. Where is the rupture disc located?
on top of chiller evaporator shell
1
,1. When repairing a refrigeration system, a swaging tool set would be used to
carry out which of the following operations?
Swaging tools can be used to expand an end of one tube to fit onto a tube of the
same original outside diameter.
2. In a refrigeration system that is not protected by a water failure switch, if the
cooling water to the condenser fails, what will be the result for protective
purposes?
the compressor will shut down by the action of the high-pressure cutout switch
6. During the initial cooling down of a box temperature in a refrigeration system,
which of the devices listed is used to prevent excessive gas pressure at the
compressor suction for the purpose of prevention of overloading of the
compressor driver?
Crankcase pressure regulator
7. A reheater in an air conditioning system performs what function?
restores the conditioned air temperature to a comfortable level
8. What is one benefit of maintenance of proper air circulation in an air
conditioned cargo space?
reduced slime and mold
9. In a two stage centrifugal air conditioning system, the liquid refrigerant passes
through the condenser directly to what component?
economizer
13. Heat is removed from the refrigerant circulating through the refrigeration
system, shown in the illustration, by which component? Illustration GS-RA-12
B
2
,14. Sea water or low temperature central fresh water is typically provided to a
ship's stores refrigeration plant for what purpose?
condense the refrigerant gas
15. Zinc plates commonly found in refrigeration systems and used as sacrificial
anodes are located where?
salt water side of the condenser
16. Vapor bubbles present in the liquid upon arrival to the thermal expansion
valve in a refrigeration system may cause erosion of the expansion valve's needle
and seat. This, in turn, could cause what condition?
TXV hunting
17. Moisture entering a typical refrigeration system will most likely produce what
effect?
freeze in the expansion valve
18. A small obstruction at the thermostatic expansion valve inlet will result in
which of the following conditions?
Lower than normal suction pressure.
19. An obstructed expansion valve may be indicated by an incompletely cooled
evaporator and what other symptom?
frosting at the evaporator inlet
20. Which of the following conditions will occur if the power element of the
thermostatic expansion valve shown in the illustration loses its charge? Illustration
GS RA-07
The valve will fail closed, providing no cooling capacity.
21. If the needle and seat assembly is excessively eroded, the valve cage assembly
can be replaced. In replacing the original valve cage assembly rated at 1/2 tons,
what would be the result if the replacement valve cage was oversized at 5 tons?
Illustration GS-RA-07
3
, The expansion valve would hunt excessively, alternately starving and overfeeding
the evaporator coil.
22. If the superheat value of the thermostatic expansion valve is adjusted too
high, what would be the result?
the suction line of the compressor will be abnormally warm
23. If the superheat setting of a thermostatic expansion valve is set too low, what
would be the result, assuming that the system has a single evaporator?
the suction line will be abnormally cold and liquid may flood back to the
compressor
24. Which of the illustrated valves is used to gain access to a hermetic system and
features a Schrader core valve which is unseated by the core depressor of hose
fitting when attached? Illustration GS-RA-69
D
25. How should small appliances with less than three pounds of refrigerant be
charged with refrigerant?
vapor charged
26. Before charging a refrigeration unit, unless quick disconnect fittings are used,
the refrigerant charging hoses should be prepared in what way?
they should be purged with refrigerant
27. Which of the illustrated devices would be the LEAST accurate for the purposes
of weighing-in a refrigerant charge? Illustration GS-RA-45
C
28. Concerning the charging of refrigerant into a vapor compression refrigerating
system, which of the following is true?
when charging as a liquid it should be to the high side only
4
