NATE A/C Exam #1 Questions and Answers
1.Low airflow over a residential split system air conditioning
evaporator can cause
A: Liquid flood-back to the
compressor B: A decrease in
compression ratio
C: An increase in suction line superheat
D: Oil logging in the evaporator
ANS: A: Liquid flood-back to the compressor
2.Which of the following is the correct sequence of work?
A: Attach gauge manifold, recover refrigerant, replace filter core,
evacuate the system, recharge the system.
B: Recover refrigerant, evacuate the system, replace filter core,
recharge the system.
C: Attach gauge manifold, evacuate the system, replace filter
core, recover refrigerant, recharge the system.
D: Attach gauge manifold, recharge the system, evacuate the
system, replace filter core.
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,ANS: A: Attach gauge manifold, recover refrigerant, replace filter core,
evac- uate the system, recharge the system.
3.As the pressure on a liquid is increased, the vaporization
temperature of the liquid
A:
Decreases
B:
Increases
C: Remains unchanged
D: Varies
ANS: B: Increases
4.An oil separator must be
mounted A: Level
B: Below the compressor crankcase
C: Above the compressor crankcase
D: In the suction line
ANS: A: Level
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, 5.Which of the following metering devices controls evaporator
pressure?
A: Thermostatic expansion
valve B: Fixed orifice
C: Low side float
D: None of these
ANS: D: None of these
An automatic expansion valve controls evaporator pressure.
6.The purpose of the external equalizer on a thermostatic
expansion valve is A: To equalize evaporator pressure drop
with respect to the TEV
B: To equalize the evaporator
pressure drop C: To help prevent
liquid floodback
D: To allow the high side pressure to equalize to the low side
when the compressor cycles off
ANS: A: To equalize evaporator pressure drop with respect to the TEV
7.The higher the MERV rating of a filter-drier, the
A: More efficient the drier at absorbing
moisture B: Less efficient the drier at
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1.Low airflow over a residential split system air conditioning
evaporator can cause
A: Liquid flood-back to the
compressor B: A decrease in
compression ratio
C: An increase in suction line superheat
D: Oil logging in the evaporator
ANS: A: Liquid flood-back to the compressor
2.Which of the following is the correct sequence of work?
A: Attach gauge manifold, recover refrigerant, replace filter core,
evacuate the system, recharge the system.
B: Recover refrigerant, evacuate the system, replace filter core,
recharge the system.
C: Attach gauge manifold, evacuate the system, replace filter
core, recover refrigerant, recharge the system.
D: Attach gauge manifold, recharge the system, evacuate the
system, replace filter core.
1/
28
,ANS: A: Attach gauge manifold, recover refrigerant, replace filter core,
evac- uate the system, recharge the system.
3.As the pressure on a liquid is increased, the vaporization
temperature of the liquid
A:
Decreases
B:
Increases
C: Remains unchanged
D: Varies
ANS: B: Increases
4.An oil separator must be
mounted A: Level
B: Below the compressor crankcase
C: Above the compressor crankcase
D: In the suction line
ANS: A: Level
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28
, 5.Which of the following metering devices controls evaporator
pressure?
A: Thermostatic expansion
valve B: Fixed orifice
C: Low side float
D: None of these
ANS: D: None of these
An automatic expansion valve controls evaporator pressure.
6.The purpose of the external equalizer on a thermostatic
expansion valve is A: To equalize evaporator pressure drop
with respect to the TEV
B: To equalize the evaporator
pressure drop C: To help prevent
liquid floodback
D: To allow the high side pressure to equalize to the low side
when the compressor cycles off
ANS: A: To equalize evaporator pressure drop with respect to the TEV
7.The higher the MERV rating of a filter-drier, the
A: More efficient the drier at absorbing
moisture B: Less efficient the drier at
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28
