NATE ELECTRICAL TECHNICIAN STUDY
GUIDE PDF 2026 HVAC ELECTRICAL
PRACTICE QUESTIONS SOLUTIONS
◉ Which of the following is not the product of incomplete combustion:
Answer: Oxides of
nitrogen
◉ An oil trap is required at the base of the discharge line of the vertical
riser is _____ or
above Answer: 8 feet
◉ A diode allows current to flow in one direction: Answer: True
◉ 1 Watt = _____ Btu Answer: 3.41
◉ Current in a closed circuit is limited by which of the following:
Answer: resistance
◉ An oil separator is located in the _____: Answer: Discharge line
◉ ______ is the heat that is absorbed or extracted when a substance
changes its state:
Answer: Latent heat
◉ _______ is the temperature at which oil starts to produce a waxy
substance that may
interfere with the refrigeration system: Answer: Floc Point
◉ 1 kWh of electric power is equivalent to ______ Btu per hour:
Answer: 3412
◉ What will be the resistance in the circuit if the supply voltage is 30V
and current flowing
,through the circuit is 5A: Answer: 6 OHM
◉ Gas valves operate at _____ voltage: Answer: 24V
◉ _______ use two special helical rotors that introduce suction vapors
then compress
them: Answer: Screw Compressor
◉ A high pressure steam boiler operates at a pressure greater than
______ : Answer: 15
PSIG
◉ In Fire tube boiler, which of the following pass through the tubes:
Answer: Flue Gas
◉ 1 kilo watt = ______ Btu Answer: 3140 BTU
◉ Turning the TXV valve stem in _______ direction increases super
heat: Answer: Clockwise
◉ Which of the following compressor uses pistons, cylinders and valves
to compress the
refrigerant gas: Answer: Reciprocating Compressor
◉ Most of the heat transfer from the heat exchanger is by which of the
following: Answer:
Convection
◉ Relays and contactors are ____ control switches: Answer: Electrically
Operated
◉ Which of the following law states that the total pressure of a confined
mixture of gases is
the sum of pressures of each of the gases in the mixture: Answer:
Daltons Law
,◉ At 32°F, 1 lb of ice can be changed to 1 lb of water by adding ____
Btu Answer: 144 BTU
◉ Which of the following circuit does not have multiple paths for
current flow: Answer:
series
◉ Dual voltage three phase motor has _____ number of terminals
Answer: 9
◉ Which one of the following is known as the line that connects
between the metering
device and the evaporator: Answer: Inlet line
◉ Approximately _____ voltage is required for creating a spark on a
spark ignition system:
Answer: 15,000V
◉ Which one of the following in the refrigeration cycle changes the
refrigerant from low
pressure gas to high pressure gas: Answer: Compressor
◉ Heat transfer that takes place in liquids and gases in which of the
following: Answer:
Convection
◉ Which of the following is used to measure the pressure drop across
the air filter: Answer:
Manometer
◉ What will be typical range of the current sensor: Answer: 4-20 mA
◉ RTD which measure temperature have a positive temperature
coefficient: Answer: True
, ◉ ______ temperature is the temperature is the temperature below
which moisture
condense out of air Answer: Dew Bulb
◉ Curved boundary In Psychrometric chart indicates which of the
following: Answer: Dew
point temperature line
◉ _____ is a combination of both sensible heat and latent heat: Answer:
Enthalpy
◉ The heat energy change that is associated with a change in the phase
(state) is: Answer:
Latent Heat
◉ In water-tube boilers, pressures range from ______ : Answer: 50 to
5,000 psig
◉ Which one of the following is used in systems for pressurizing the
building: Answer:
Exhaust or relief dampers
◉ The temperature-resistance characteristic of a thermistor is
_________ : Answer: Non
linear
◉ At _________ this superheated refrigerant vapor pressure and
temperature is added:
Answer: Compressor
◉ For every 1000 feet above sea level,the capacity of a natural gas
furnace is de-rated by
_______ Answer: 4%
GUIDE PDF 2026 HVAC ELECTRICAL
PRACTICE QUESTIONS SOLUTIONS
◉ Which of the following is not the product of incomplete combustion:
Answer: Oxides of
nitrogen
◉ An oil trap is required at the base of the discharge line of the vertical
riser is _____ or
above Answer: 8 feet
◉ A diode allows current to flow in one direction: Answer: True
◉ 1 Watt = _____ Btu Answer: 3.41
◉ Current in a closed circuit is limited by which of the following:
Answer: resistance
◉ An oil separator is located in the _____: Answer: Discharge line
◉ ______ is the heat that is absorbed or extracted when a substance
changes its state:
Answer: Latent heat
◉ _______ is the temperature at which oil starts to produce a waxy
substance that may
interfere with the refrigeration system: Answer: Floc Point
◉ 1 kWh of electric power is equivalent to ______ Btu per hour:
Answer: 3412
◉ What will be the resistance in the circuit if the supply voltage is 30V
and current flowing
,through the circuit is 5A: Answer: 6 OHM
◉ Gas valves operate at _____ voltage: Answer: 24V
◉ _______ use two special helical rotors that introduce suction vapors
then compress
them: Answer: Screw Compressor
◉ A high pressure steam boiler operates at a pressure greater than
______ : Answer: 15
PSIG
◉ In Fire tube boiler, which of the following pass through the tubes:
Answer: Flue Gas
◉ 1 kilo watt = ______ Btu Answer: 3140 BTU
◉ Turning the TXV valve stem in _______ direction increases super
heat: Answer: Clockwise
◉ Which of the following compressor uses pistons, cylinders and valves
to compress the
refrigerant gas: Answer: Reciprocating Compressor
◉ Most of the heat transfer from the heat exchanger is by which of the
following: Answer:
Convection
◉ Relays and contactors are ____ control switches: Answer: Electrically
Operated
◉ Which of the following law states that the total pressure of a confined
mixture of gases is
the sum of pressures of each of the gases in the mixture: Answer:
Daltons Law
,◉ At 32°F, 1 lb of ice can be changed to 1 lb of water by adding ____
Btu Answer: 144 BTU
◉ Which of the following circuit does not have multiple paths for
current flow: Answer:
series
◉ Dual voltage three phase motor has _____ number of terminals
Answer: 9
◉ Which one of the following is known as the line that connects
between the metering
device and the evaporator: Answer: Inlet line
◉ Approximately _____ voltage is required for creating a spark on a
spark ignition system:
Answer: 15,000V
◉ Which one of the following in the refrigeration cycle changes the
refrigerant from low
pressure gas to high pressure gas: Answer: Compressor
◉ Heat transfer that takes place in liquids and gases in which of the
following: Answer:
Convection
◉ Which of the following is used to measure the pressure drop across
the air filter: Answer:
Manometer
◉ What will be typical range of the current sensor: Answer: 4-20 mA
◉ RTD which measure temperature have a positive temperature
coefficient: Answer: True
, ◉ ______ temperature is the temperature is the temperature below
which moisture
condense out of air Answer: Dew Bulb
◉ Curved boundary In Psychrometric chart indicates which of the
following: Answer: Dew
point temperature line
◉ _____ is a combination of both sensible heat and latent heat: Answer:
Enthalpy
◉ The heat energy change that is associated with a change in the phase
(state) is: Answer:
Latent Heat
◉ In water-tube boilers, pressures range from ______ : Answer: 50 to
5,000 psig
◉ Which one of the following is used in systems for pressurizing the
building: Answer:
Exhaust or relief dampers
◉ The temperature-resistance characteristic of a thermistor is
_________ : Answer: Non
linear
◉ At _________ this superheated refrigerant vapor pressure and
temperature is added:
Answer: Compressor
◉ For every 1000 feet above sea level,the capacity of a natural gas
furnace is de-rated by
_______ Answer: 4%
