HVAC CONTRACTOR EXAM 2026/2027 | PRACTICE QUESTIONS &
CORRECT ANSWERS | COMPLETE EXAM PREP GUIDE
1. If a residential thermostat is malfunctioning and not sending the correct
control voltage, what might be the immediate consequence for the HVAC
system?
The HVAC system may fail to turn on or off as needed.
The thermostat will display an error message.
The thermostat will require a new battery.
The HVAC system will operate at maximum capacity continuously.
2. What is the heating load of a building?
the hourly rate of net heat gain in an enclosed space
the daily rate of net heat loss and calculated in BTU
the hourly rate of net heat loss in an enclosed space
the daily rate of net heat gain and calculated in BTU
3. If the window area in the bath were to increase to 30 square feet, how would
you estimate the new net winter heat loss, assuming it scales linearly with
area?
450 btuh
1324 btuh
900 btuh
178 btuh
4. ____ is the number used to indicate resistance to heat transfer.
, U-value
BTU/H
R-value
C-value
5. In a scenario where outdoor temperatures are mild, how would the use of an
economizer affect the overall energy costs of an HVAC system?
It would lower energy costs by reducing the need for mechanical
cooling.
It would raise energy costs by requiring more maintenance.
It would increase energy costs due to additional fan usage.
It would have no effect on energy costs.
6. If the net summer heat gain through the east exterior wall of bedroom 1
increases to 200 btuh, what adjustments should be made to the HVAC system
to maintain comfort levels?
Install additional heating elements.
Increase the cooling capacity of the HVAC system.
Decrease the insulation in the wall.
Reduce the size of the HVAC system.
7. Describe the relationship between boiling temperature and pressure in
refrigerants.
Increased boiling temperature results in a decrease in latent heat only.
As the boiling temperature of refrigerants increases, the pressure
also increases due to the properties of gases.
, The boiling temperature has no effect on the pressure of refrigerants.
Higher boiling temperatures lead to lower pressures in refrigerants.
8. Describe the importance of using tamper resistant caps on outdoor
refrigerant circuit access ports in HVAC systems.
Tamper resistant caps protect the refrigerant from unauthorized
access and potential leaks.
Tamper resistant caps are used solely for aesthetic purposes.
Tamper resistant caps are required by law for all HVAC installations.
Tamper resistant caps improve the efficiency of the HVAC system.
9. Describe the role of a ground fault circuit interrupter in electrical safety for
technicians.
A ground fault circuit interrupter is used to extend the reach of power
tools safely.
A ground fault circuit interrupter helps prevent electrocution by
interrupting the electrical circuit when it detects an imbalance in the
current.
A ground fault circuit interrupter measures voltage levels in power
tools.
A ground fault circuit interrupter is a type of power tool.
10. If a contractor mistakenly uses a .019 gauge connector instead of the
required .029 gauge for a low heat appliance, what potential issues could
arise?
The appliance would operate more efficiently with the thinner gauge.
No issues would arise as both gauges are interchangeable.
, Increased risk of failure or safety hazards due to inadequate
support and heat resistance.
The installation would be more cost-effective with the thinner gauge.
11. A 10' x 10' wall with an R value of 11 and a temperature difference of 35
degrees would have a transmission loss of?
546 btuh
315 btuh
38,500 btuh
1245 btuh
12. Generally speaking the ratio of return air to supply air should be
2 to 1
.8 to 1
1 to 1.5
1 to 1
13. What is the primary focus of manual D in HVAC systems?
Designing a proper duct system for commercial application
Designing the correct fans and controls for a system
Properly designing an air distribution system for residential using
the blower supplied with the equipment
Matching the system size to the existing duct system
14. What is the recommended frequency for applying cutting oil when hand
threading steel pipe?
CORRECT ANSWERS | COMPLETE EXAM PREP GUIDE
1. If a residential thermostat is malfunctioning and not sending the correct
control voltage, what might be the immediate consequence for the HVAC
system?
The HVAC system may fail to turn on or off as needed.
The thermostat will display an error message.
The thermostat will require a new battery.
The HVAC system will operate at maximum capacity continuously.
2. What is the heating load of a building?
the hourly rate of net heat gain in an enclosed space
the daily rate of net heat loss and calculated in BTU
the hourly rate of net heat loss in an enclosed space
the daily rate of net heat gain and calculated in BTU
3. If the window area in the bath were to increase to 30 square feet, how would
you estimate the new net winter heat loss, assuming it scales linearly with
area?
450 btuh
1324 btuh
900 btuh
178 btuh
4. ____ is the number used to indicate resistance to heat transfer.
, U-value
BTU/H
R-value
C-value
5. In a scenario where outdoor temperatures are mild, how would the use of an
economizer affect the overall energy costs of an HVAC system?
It would lower energy costs by reducing the need for mechanical
cooling.
It would raise energy costs by requiring more maintenance.
It would increase energy costs due to additional fan usage.
It would have no effect on energy costs.
6. If the net summer heat gain through the east exterior wall of bedroom 1
increases to 200 btuh, what adjustments should be made to the HVAC system
to maintain comfort levels?
Install additional heating elements.
Increase the cooling capacity of the HVAC system.
Decrease the insulation in the wall.
Reduce the size of the HVAC system.
7. Describe the relationship between boiling temperature and pressure in
refrigerants.
Increased boiling temperature results in a decrease in latent heat only.
As the boiling temperature of refrigerants increases, the pressure
also increases due to the properties of gases.
, The boiling temperature has no effect on the pressure of refrigerants.
Higher boiling temperatures lead to lower pressures in refrigerants.
8. Describe the importance of using tamper resistant caps on outdoor
refrigerant circuit access ports in HVAC systems.
Tamper resistant caps protect the refrigerant from unauthorized
access and potential leaks.
Tamper resistant caps are used solely for aesthetic purposes.
Tamper resistant caps are required by law for all HVAC installations.
Tamper resistant caps improve the efficiency of the HVAC system.
9. Describe the role of a ground fault circuit interrupter in electrical safety for
technicians.
A ground fault circuit interrupter is used to extend the reach of power
tools safely.
A ground fault circuit interrupter helps prevent electrocution by
interrupting the electrical circuit when it detects an imbalance in the
current.
A ground fault circuit interrupter measures voltage levels in power
tools.
A ground fault circuit interrupter is a type of power tool.
10. If a contractor mistakenly uses a .019 gauge connector instead of the
required .029 gauge for a low heat appliance, what potential issues could
arise?
The appliance would operate more efficiently with the thinner gauge.
No issues would arise as both gauges are interchangeable.
, Increased risk of failure or safety hazards due to inadequate
support and heat resistance.
The installation would be more cost-effective with the thinner gauge.
11. A 10' x 10' wall with an R value of 11 and a temperature difference of 35
degrees would have a transmission loss of?
546 btuh
315 btuh
38,500 btuh
1245 btuh
12. Generally speaking the ratio of return air to supply air should be
2 to 1
.8 to 1
1 to 1.5
1 to 1
13. What is the primary focus of manual D in HVAC systems?
Designing a proper duct system for commercial application
Designing the correct fans and controls for a system
Properly designing an air distribution system for residential using
the blower supplied with the equipment
Matching the system size to the existing duct system
14. What is the recommended frequency for applying cutting oil when hand
threading steel pipe?
