HVAC NATE Heat Pump Exam (Latest 2024/ 2025 Update) 100% Correct Questions and Verified Answers| Grade A

HVAC NATE Heat Pump Exam (Latest
2024/ 2025 Update) 100% Correct Questions
and Verified Answers| Grade A
Q: What is the absolute pressure at sea level if a gauge pressure is 35 psig?
Answer:
49.7psia
Q: 100,000 BTUH output furnace.
Return air temp is 65F.
Supply air is 135F.
What is the CFM?
Answer:
1323CFM
Q: What is the best method of repair when a residential supply diffuser is noisy because of a
loose vane?
Answer:
Replace the diffuser.
Q: When performing preventive maintenance on a heat pump what should the technician check
and why?
Answer:
Outdoor fan. To be certain it runs freely with no binding.

Q: What is the effect of 170 volts supplied to a 208/230 volt compressor?
Answer:
Would cause the current to increase and the motor may trip on overload.
Q: On a service call for a cooling problem with a heat pump, your inspections find a liquid line
that has condensation on it. What is most likely to cause this?
Answer:
Restriction in the liquid line.
Q: What is a reason for cool air complaints when a heat pump is operating in the heating cycle?
Answer:
Excessive supply air velocities.
Q: The following measurements are recorded on an operating heat pump system. The heat
pump is operating with the compressor only with no auxiliary heat:
• Heat pump only supply air temperature 92°F
• Heat pump only return air temperature 70°F
• Outdoor temperature 54°F
• Supply air temp. /auxiliary heat ON 115°F
• Return air temp. /auxiliary heat ON 70°F
• CFM 1228
What is the heating capacity in BTUH?
Answer:
29,177 BTU/H

Q: Inadequate heating can be caused by what?
Answer:
Dirty or clogged air filter.
Q: To minimize noise problems in residential duct systems, what is the range (recommended to
maximum) of design air velocity in the rectangular main supply trunk?
Answer:
700 to 900 fpm
Q: conditions while checking a packaged heat pump in cooling.
• The unit has a piston type metering device on both the indoor and outdoor coils.
• Outdoor temperature 75°F
• Superheat 55°F
What is wrong with the system?
Answer:
Undercharged.
Q: What will you get when a capillary tube is overcharged?
Answer:
low superheat and high sub cooling
Q: What is the effect of a low charge on the switchover operations of a reversing valve?

Answer:
Reversing valves are less likely to transfer if charge is low.
Q: A technician is working on a heat pump with a capacitor start-capacitor run compressor. On
initial startup, the compressor hums momentarily and the shuts down on internal overload. What
is the problem?
Answer:
Too great a pressure difference on the compressor.
Q: A step down transformer has a rating of 40 VA. Its primary voltage is 120V with a
secondary voltage of 24V. What is the maximum current draw of a load connected to this
transformer?
Answer:
1.7amps
Q: What does a bright red or orange glow from the resistance element in a duct heater indicate?
Answer:
Flow of air is insufficient.
Q: What does the outdoor fan do during defrost on a heat pump and why?
Answer:
The fan stops to minimize defrost time.
Q: What do bent vanes on a direct drive blower wheel in an air handler cause?

HVAC NATE Heat Pump Exam (New 2024/
2025 Update) Questions and Verified
Answers 100% Correct | A Grade
QUESTION
In order to troubleshoot a load controlled by a control string, what should the technician check
first?
Answer:
Proper voltage applied across the load.
QUESTION
The technician suspects that an outdoor thermostat used to bring on auxiliary heat may be out of
calibration. The thermostat is a close-on-fall type that is adjustable. What is one method for
checking the thermostat calibration?
Answer:
Manually rotate the shaft until the thermostat closes and compare the dial setting to an accurate
outdoor temperature reading plus 10°F
QUESTION
When must the installer must be certain to plumb the cabinet so its sides are vertical?
Answer:
When changing out an evaporator coil.
QUESTION

What is the recommended maximum external static pressure used for heating and cooling
equipment with blowers for 5 ton of cooling or less?
Answer:
0.1 in W.C
QUESTION
When a balancing check of a newly installed duct what needs to happen?
Answer:
Dampers should be open completely in all rooms.
QUESTION
Why is operating sound is a consideration in the location of a condensing unit?
Answer:
Because excessive noise could be disruptive to the customer
QUESTION
A technician has determined a supply in a flexible duct system is leaking. What should be
checked?
Answer:
All connections inner and outer layers.
QUESTION
What is sensible heat ratio?
Answer:
sensible removed ÷ total heat removed

QUESTION
Service site conditions are:
• House feels "drafty" in cooling
• 3½ ton split system
• High supply face velocities
• Ductwork is properly sized
• Total CFM 1400
What does this indicate?
Answer:
These readings indicate the system is operating normally but the supply registers are too
restrictive
QUESTION
When a wet bulb reading is very close to the dry bulb reading from the same instrument, what
does this indicate?
Answer:
Relative humidity is high.
QUESTION
What measurements would be needed to properly evaluate a complaint of "drafty" operation
with a heating system?
Answer:
System TD, Drop, and Static Pressure
QUESTION
What kind of energy does the condenser remove from the refrigerant?

Answer:
Sensible heat and Latent heat
QUESTION
Where does refrigerant boil?
Answer:
In the Evaporator.
QUESTION
What is the common suction line on a heat pump connected to?
Answer:
The indoor coil and the compressor.
QUESTION
What are the two generally used methods for changing capacity on demand in a heat pump?
Answer:
Two speed compressor. Two stage thermostat
QUESTION
What are the three things that happen when a heat pump is cycled into the defrost mode?
Answer:
Reversing valve switches to cooling mode, Outdoor fan is shut off, and auxiliary heat is
energized.