Nate ac UPDATED ACTUAL QUESTIONS WITH CORRECT
ANSWERS
Question 1.
The primary purpose of using flux when soldering copper or brass parts is to:
ANSWER
prevent oxidation.
Question 2.
Light commercial outdoor condensing units that are installed in geographic areas where snowfalls can
be heavy must be mounted:
ANSWER
with wind barriers on all sides.
Question 3.
Proper ductwork connections and sealing is critical to good system performance. Conditions are:
Return side air leak of 15 % in a ventilated attic 2.5 ton system rated at 1,000 CFM. Attic Air 95°F The
loss in delivered capacity is equal to:.
ANSWER
Ratio of air leakage to total air
Question 4.
An important consideration when instailing a motorized economizer is to check to be certain that:
ANSWER
open the vanes operate without binding.
Question 5.
Electronic leak detectors typicalily have a push-button or knob for setting a reference refrigerant level.
This feature is useful for:
ANSWER
setting the detector for use in environments with ambient refrigerant vapor.
1/8
, Question 6.
When checking the pressures in an operating system with a manifold gauge set, refrigerant oil in a
hose will:
ANSWER
have no effect on the gauge reading.
Question 7.
Which of the following is used to measure air pressure?
ANSWER
diaphragm type differential pressure gauge
Question 8.
A technician measures the return air temperature of a 100,000 Btu output oil furnace to be 65°F and
the supply side air temperature is 135°F. What is the CFM?
ANSWER
1323
Question 9.
What steps are necessary to clean a two row curved condenser coil?
ANSWER
separate the two rows of coils, spray all surfaces with proper coil cleaner and water flush
Question 10.
A residential supply diffuser that is noisy because of a loose vane is best serviced by:
ANSWER
replacing the diffuser.
Question 11.
A system airflow check is used to diagnose: p
ANSWER
humidity problems.
2/8
ANSWERS
Question 1.
The primary purpose of using flux when soldering copper or brass parts is to:
ANSWER
prevent oxidation.
Question 2.
Light commercial outdoor condensing units that are installed in geographic areas where snowfalls can
be heavy must be mounted:
ANSWER
with wind barriers on all sides.
Question 3.
Proper ductwork connections and sealing is critical to good system performance. Conditions are:
Return side air leak of 15 % in a ventilated attic 2.5 ton system rated at 1,000 CFM. Attic Air 95°F The
loss in delivered capacity is equal to:.
ANSWER
Ratio of air leakage to total air
Question 4.
An important consideration when instailing a motorized economizer is to check to be certain that:
ANSWER
open the vanes operate without binding.
Question 5.
Electronic leak detectors typicalily have a push-button or knob for setting a reference refrigerant level.
This feature is useful for:
ANSWER
setting the detector for use in environments with ambient refrigerant vapor.
1/8
, Question 6.
When checking the pressures in an operating system with a manifold gauge set, refrigerant oil in a
hose will:
ANSWER
have no effect on the gauge reading.
Question 7.
Which of the following is used to measure air pressure?
ANSWER
diaphragm type differential pressure gauge
Question 8.
A technician measures the return air temperature of a 100,000 Btu output oil furnace to be 65°F and
the supply side air temperature is 135°F. What is the CFM?
ANSWER
1323
Question 9.
What steps are necessary to clean a two row curved condenser coil?
ANSWER
separate the two rows of coils, spray all surfaces with proper coil cleaner and water flush
Question 10.
A residential supply diffuser that is noisy because of a loose vane is best serviced by:
ANSWER
replacing the diffuser.
Question 11.
A system airflow check is used to diagnose: p
ANSWER
humidity problems.
2/8
