Idaho Heating Contractor Qualification
Advanced 100-Question Practice Exam
2026 | Questions & Answers with
Detailed Rationales | Complete Exam
Prep & Study Guide
1. Which Idaho license category most directly authorizes a contractor to
perform general HVAC work, including heating installations within the scope of
the license?
A. Limited Heating Specialty Contractor
B. HVAC Specialty Contractor
C. HVAC Contractor
D. HVAC Apprentice
Answer: HVAC Contractor
Rationale: The Idaho HVAC Contractor license is the broad contractor
classification for HVAC work. Specialty and limited-heating classifications have
narrower scopes.
2. What bond amount must an Idaho HVAC contractor provide after passing the
required examination?
,A. $500
B. $1,000
C. $2,000
D. $5,000
Answer: $2,000
Rationale: Idaho DOPL states that applicants for an HVAC contractor license
must provide proof of a $2,000 HVAC contractor bond.
3. Which organization currently administers Idaho HVAC contractor
examinations?
A. ICC
B. PSI
C. Prometric
D. Pearson VUE
Answer: PSI
Rationale: Idaho DOPL states that HVAC examinations are currently offered
through PSI.
4. Which code is specifically identified by Idaho DOPL as a current HVAC code?
A. 2021 IMC
B. 2024 IMC
C. 2018 IMC
D. 2015 IMC
Answer: 2018 International Mechanical Code
Rationale: Idaho DOPL currently lists the 2018 International Mechanical Code as
an adopted HVAC code.
5. Which code is particularly important when installing natural-gas-fired
furnaces and other fuel-gas appliances?
,A. International Plumbing Code
B. International Fuel Gas Code
C. International Energy Conservation Code only
D. International Existing Building Code
Answer: International Fuel Gas Code
Rationale: Fuel-gas appliance installation, combustion air, gas piping, venting,
and related requirements are addressed by the fuel-gas provisions adopted by
the jurisdiction. Idaho identifies the 2018 IFGC as a current HVAC code.
6. What is the primary purpose of a furnace heat exchanger?
A. Increase gas pressure
B. Transfer heat while keeping combustion products separated from circulating air
C. Increase blower speed
D. Reduce electrical resistance
Answer: Transfer heat while keeping combustion products separated from
circulating air
Rationale: The heat exchanger transfers combustion heat to the air stream
while preventing combustion gases from entering occupied-space air.
7. A furnace has a cracked heat exchanger. What is the most serious concern?
A. Reduced thermostat accuracy
B. Increased blower noise
C. Possible combustion-gas contamination of the air stream
D. Excessive filter efficiency
Answer: Possible combustion-gas contamination of the air stream
Rationale: A compromised heat exchanger can allow combustion products,
potentially including carbon monoxide, to enter the circulating-air system.
8. What is the primary function of a furnace limit control?
, A. Maintain gas pressure
B. Prevent excessive furnace temperature
C. Control outdoor humidity
D. Measure refrigerant pressure
Answer: Prevent excessive furnace temperature
Rationale: The high-limit control protects the furnace from unsafe overheating
caused by inadequate airflow, excessive firing, blower problems, or other
conditions.
9. If a furnace repeatedly trips its high-limit control, the contractor should first
investigate:
A. Increasing the gas input
B. Airflow and temperature rise
C. Removing the limit control
D. Increasing thermostat voltage
Answer: Airflow and temperature rise
Rationale: Restricted airflow, dirty filters, undersized ductwork, blower
problems, and excessive firing can cause excessive temperature rise and
repeated limit operation.
10. What is the purpose of measuring furnace temperature rise?
A. Determine electrical phase sequence
B. Verify that the furnace operates within its specified heating range
C. Calculate refrigerant charge
D. Determine gas-pipe material
Answer: Verify that the furnace operates within its specified heating range
Rationale: Temperature rise is the difference between return-air and supply-air
temperatures and is compared with the manufacturer's listed operating range.
Advanced 100-Question Practice Exam
2026 | Questions & Answers with
Detailed Rationales | Complete Exam
Prep & Study Guide
1. Which Idaho license category most directly authorizes a contractor to
perform general HVAC work, including heating installations within the scope of
the license?
A. Limited Heating Specialty Contractor
B. HVAC Specialty Contractor
C. HVAC Contractor
D. HVAC Apprentice
Answer: HVAC Contractor
Rationale: The Idaho HVAC Contractor license is the broad contractor
classification for HVAC work. Specialty and limited-heating classifications have
narrower scopes.
2. What bond amount must an Idaho HVAC contractor provide after passing the
required examination?
,A. $500
B. $1,000
C. $2,000
D. $5,000
Answer: $2,000
Rationale: Idaho DOPL states that applicants for an HVAC contractor license
must provide proof of a $2,000 HVAC contractor bond.
3. Which organization currently administers Idaho HVAC contractor
examinations?
A. ICC
B. PSI
C. Prometric
D. Pearson VUE
Answer: PSI
Rationale: Idaho DOPL states that HVAC examinations are currently offered
through PSI.
4. Which code is specifically identified by Idaho DOPL as a current HVAC code?
A. 2021 IMC
B. 2024 IMC
C. 2018 IMC
D. 2015 IMC
Answer: 2018 International Mechanical Code
Rationale: Idaho DOPL currently lists the 2018 International Mechanical Code as
an adopted HVAC code.
5. Which code is particularly important when installing natural-gas-fired
furnaces and other fuel-gas appliances?
,A. International Plumbing Code
B. International Fuel Gas Code
C. International Energy Conservation Code only
D. International Existing Building Code
Answer: International Fuel Gas Code
Rationale: Fuel-gas appliance installation, combustion air, gas piping, venting,
and related requirements are addressed by the fuel-gas provisions adopted by
the jurisdiction. Idaho identifies the 2018 IFGC as a current HVAC code.
6. What is the primary purpose of a furnace heat exchanger?
A. Increase gas pressure
B. Transfer heat while keeping combustion products separated from circulating air
C. Increase blower speed
D. Reduce electrical resistance
Answer: Transfer heat while keeping combustion products separated from
circulating air
Rationale: The heat exchanger transfers combustion heat to the air stream
while preventing combustion gases from entering occupied-space air.
7. A furnace has a cracked heat exchanger. What is the most serious concern?
A. Reduced thermostat accuracy
B. Increased blower noise
C. Possible combustion-gas contamination of the air stream
D. Excessive filter efficiency
Answer: Possible combustion-gas contamination of the air stream
Rationale: A compromised heat exchanger can allow combustion products,
potentially including carbon monoxide, to enter the circulating-air system.
8. What is the primary function of a furnace limit control?
, A. Maintain gas pressure
B. Prevent excessive furnace temperature
C. Control outdoor humidity
D. Measure refrigerant pressure
Answer: Prevent excessive furnace temperature
Rationale: The high-limit control protects the furnace from unsafe overheating
caused by inadequate airflow, excessive firing, blower problems, or other
conditions.
9. If a furnace repeatedly trips its high-limit control, the contractor should first
investigate:
A. Increasing the gas input
B. Airflow and temperature rise
C. Removing the limit control
D. Increasing thermostat voltage
Answer: Airflow and temperature rise
Rationale: Restricted airflow, dirty filters, undersized ductwork, blower
problems, and excessive firing can cause excessive temperature rise and
repeated limit operation.
10. What is the purpose of measuring furnace temperature rise?
A. Determine electrical phase sequence
B. Verify that the furnace operates within its specified heating range
C. Calculate refrigerant charge
D. Determine gas-pipe material
Answer: Verify that the furnace operates within its specified heating range
Rationale: Temperature rise is the difference between return-air and supply-air
temperatures and is compared with the manufacturer's listed operating range.
