NATE HEAT PUMP ACTUAL TEST PAPER
2026 QUESTIONS WITH SOLUTIONS
GRADED A+
◉What is the primary purpose of using flux when soldering copper
or brass parts? Answer: Prevent Oxidation
◉The water that results from a defrost cycle of an air to air heat
pump(runoff) must? Answer: Drain off and away from the outdoor
coil.
◉Why must the runoff be drained off and away from the outdoor
coil? Answer: Excessive ice can build up on the bottom of the coil
and can reduce capacity.
◉What is the component that reduces sound transmission and
prevents water leaks of a package heat pump installed on a roof?
Answer: Curb Gasket
◉Why do you need to add a control for a heat pump indoor coil that
is installed on a fossil fuel furnace? Answer: So the heat pump and
furnace do not operate at the same time in normal heating.
,◉What happens when you energize a hermetic refrigeration
compressor and the system is in a deep vacuum? Answer: Motor
windings could become damaged.
◉What needs to happen in order to consider an evacuation to be
complete? Answer: System should be evacuated to a vacuum of 500
Microns or below.
◉A system is supplied from the factory with charge for a 15 foot line
set. The data plate shows the required system charge to be 5 pounds
10 ounces. The line set uses a 3/8 inch liquid line and is 25 feet long.
The manufacturer's instruction sheet specifies 0.6 ounces of
refrigerant to be added for each added foot of refrigerant line length.
How much refrigerant is needed to completely charge the system?
Answer: 6lbs
◉Where are drive slips typically installed? Answer: On the shorter
sides of rectangular duct.
◉What is a necessary check to properly set a heat anticipator?
Answer: Heating control circuit amperage
draw.
, ◉A heat pump operating in normal ice free conditions maintains a
certain temperature difference between the outdoor coil
temperature and the surrounding outdoor ambient. What is this
temperature referred to as? Answer: Coil TD.
◉What is the smallest refrigerant leak that an electronic leak
detector should be capable of sensing? Answer: .o5oz per year.
◉When checking the pressures in an operating system with a
manifold gauge set, will refrigerant oil in a hose will have an effect
on the gauge? Answer: No
◉What is the absolute pressure at sea level if a gauge pressure is 35
psig? Answer: 49.7psia
◉100,000 BTUH output furnace.
Return air temp is 65F.
Supply air is 135F.
What is the CFM? Answer: 1323CFM
◉What is the best method of repair when a residential supply
diffuser is noisy because of a loose vane? Answer: Replace the
diffuser.
2026 QUESTIONS WITH SOLUTIONS
GRADED A+
◉What is the primary purpose of using flux when soldering copper
or brass parts? Answer: Prevent Oxidation
◉The water that results from a defrost cycle of an air to air heat
pump(runoff) must? Answer: Drain off and away from the outdoor
coil.
◉Why must the runoff be drained off and away from the outdoor
coil? Answer: Excessive ice can build up on the bottom of the coil
and can reduce capacity.
◉What is the component that reduces sound transmission and
prevents water leaks of a package heat pump installed on a roof?
Answer: Curb Gasket
◉Why do you need to add a control for a heat pump indoor coil that
is installed on a fossil fuel furnace? Answer: So the heat pump and
furnace do not operate at the same time in normal heating.
,◉What happens when you energize a hermetic refrigeration
compressor and the system is in a deep vacuum? Answer: Motor
windings could become damaged.
◉What needs to happen in order to consider an evacuation to be
complete? Answer: System should be evacuated to a vacuum of 500
Microns or below.
◉A system is supplied from the factory with charge for a 15 foot line
set. The data plate shows the required system charge to be 5 pounds
10 ounces. The line set uses a 3/8 inch liquid line and is 25 feet long.
The manufacturer's instruction sheet specifies 0.6 ounces of
refrigerant to be added for each added foot of refrigerant line length.
How much refrigerant is needed to completely charge the system?
Answer: 6lbs
◉Where are drive slips typically installed? Answer: On the shorter
sides of rectangular duct.
◉What is a necessary check to properly set a heat anticipator?
Answer: Heating control circuit amperage
draw.
, ◉A heat pump operating in normal ice free conditions maintains a
certain temperature difference between the outdoor coil
temperature and the surrounding outdoor ambient. What is this
temperature referred to as? Answer: Coil TD.
◉What is the smallest refrigerant leak that an electronic leak
detector should be capable of sensing? Answer: .o5oz per year.
◉When checking the pressures in an operating system with a
manifold gauge set, will refrigerant oil in a hose will have an effect
on the gauge? Answer: No
◉What is the absolute pressure at sea level if a gauge pressure is 35
psig? Answer: 49.7psia
◉100,000 BTUH output furnace.
Return air temp is 65F.
Supply air is 135F.
What is the CFM? Answer: 1323CFM
◉What is the best method of repair when a residential supply
diffuser is noisy because of a loose vane? Answer: Replace the
diffuser.
