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Idaho - HVAC JOURNEYMAN EXAM

Idaho  ·  PSI Services Contractor

Verified, not estimated. Every figure below is drawn from the official exam structure we maintain — question counts, passing standard and topic weighting. Practice questions are grounded in the source law with statute citations. We omit any figure we can't verify rather than guess at it.
Total questions
100
Passing score
70
Exam time
240 min
Administered by
PSI Services Contractor
Format
Reference materials allowed

Idaho State Portion 100 questions

2018 International Mechanical Code (IMC) - Chapter 1 4 Q · 4%
2018 International Mechanical Code (IMC) - Chapter 2 7 Q · 7%
2018 International Mechanical Code (IMC) - Chapter 3 9 Q · 9%
2018 International Mechanical Code (IMC) - Chapter 4 5 Q · 5%
2018 International Mechanical Code (IMC) - Chapter 5 9 Q · 9%
2018 International Mechanical Code (IMC) - Chapter 6 4 Q · 4%
2018 International Mechanical Code (IMC) - Chapter 8 4 Q · 4%
2018 International Mechanical Code (IMC) - Chapter 9 3 Q · 3%
2018 International Mechanical Code (IMC) - Chapter 10 3 Q · 3%
2018 International Mechanical Code (IMC) - Chapter 11 5 Q · 5%
2018 International Mechanical Code (IMC) - Chapter 12 5 Q · 5%
2018 International Mechanical Code (IMC) - Chapter 13 4 Q · 4%
2018 International Mechanical Code (IMC) - Chapter 14 1 Q · 1%
2018 International Fuel Gas Code (IFGC) - Chapter 1 3 Q · 3%
2018 International Fuel Gas Code (IFGC) - Chapter 2 3 Q · 3%
2018 International Fuel Gas Code (IFGC) - Chapter 3 6 Q · 6%
2018 International Fuel Gas Code (IFGC) - Chapter 4 7 Q · 7%
2018 International Fuel Gas Code (IFGC) - Chapter 5 8 Q · 8%
2018 International Fuel Gas Code (IFGC) - Chapter 6 5 Q · 5%
2018 International Fuel Gas Code (IFGC) - Chapter 7 5 Q · 5%

Key Distinctions

Type I HoodvsType II Hood

Type I hoods collect grease vapors and smoke and are equipped with a fire suppression system, while Type II hoods are general hoods for collecting steam, vapor, heat, and odors without a fire suppression requirement.

2018 International Mechanical Code (IMC), Chapter 2, Section 202
Low-Pressure Steam BoilervsLow-Pressure Hot-Water Boiler

Low-pressure steam boilers operate at pressures not exceeding 15 psi, while low-pressure hot-water boilers operate at pressures not exceeding 160 psi and temperatures not exceeding 250°F.

2018 International Mechanical Code (IMC), Chapter 2, Section 202
Brazed JointvsSoldered Joint

A brazed joint uses metallic alloys that melt above 1,000°F (538°C), while a soldered joint uses alloys that melt between 400°F (204°C) and 1,000°F (538°C).

2018 International Mechanical Code (IMC), Chapter 2, Section 202
Low-Heat AppliancevsMedium-Heat Appliance

A low-heat appliance has flue-entrance combustion products at 1,000°F or less, while a medium-heat appliance has temperatures above 1,000°F but not greater than 2,000°F.

2018 International Mechanical Code (IMC), Chapter 2, Section 202
General Requirement (IMC)vsSpecific Requirement (IMC)

When a general requirement and a specific requirement conflict, the specific requirement governs; when different sections specify different materials or methods, the most restrictive governs.

2018 International Mechanical Code (IMC), Section 102.1, Chapter 1
Permit Application AbandonmentvsPermit Expiration

A permit application is deemed abandoned 180 days after filing if not pursued in good faith or a permit is not issued, while an issued permit expires if authorized work is not commenced within 180 days of issuance or is suspended for 180 days after commencement.

2018 International Mechanical Code (IMC), Section 106.3.3, Chapter 1
Induced DraftvsNatural Draft

Induced draft uses a fan or blower located between the appliance and the chimney/vent termination to create pressure difference, while natural draft relies on the natural buoyancy of combustion gases without mechanical assistance.

2018 International Mechanical Code (IMC), Chapter 2, Section 202
High-Probability Refrigeration SystemvsDirect Refrigeration System

A high-probability system is one where a refrigerant leak from a failed component will enter an occupancy-classified area other than the machinery room, while a direct refrigeration system is one where the evaporator or condenser is in direct contact with the air or substance being conditioned.

2018 International Mechanical Code (IMC), Chapter 2, Section 202
Portable Heating Appliance (Permit Exempt)vsPermanently Installed Heating System (Permit Required)

Portable heating appliances are explicitly exempt from permit requirements under the IMC, while permanently installed mechanical systems require a permit before work commences.

2018 International Mechanical Code (IMC), Section 106.2, Chapter 1
Double Island Canopy HoodvsStandard Canopy Hood

A double island canopy hood is placed over back-to-back cooking appliance lines and is open on all sides overhanging both fronts, while a standard canopy hood serves a single appliance line.

2018 International Mechanical Code (IMC), Chapter 2, Section 202
Code Provisions vs. Referenced Standards (Conflict)vsGeneral vs. Specific Code Requirements (Conflict)

When the IMC code provisions conflict with referenced standards, the IMC code provisions apply; when a general requirement conflicts with a specific requirement within the code, the specific requirement governs.

2018 International Mechanical Code (IMC), Section 102.8.1
Class 1 Refrigerant (Flammability)vsClass IA Flammable Liquid

A Class 1 refrigerant does not show flame propagation when tested in air at 14.7 psia and 140°F, while a Class IA flammable liquid has a flash point below 73°F and a boiling point below 100°F.

2018 International Mechanical Code (IMC), Chapter 2, Section 202

Key Terms

Purpose of the IMC (Section 101.3) 2018 International Mechanical Code (IMC), Section 101.3, Chapter 1
The 2018 IMC, Section 101.3 establishes minimum standards to provide a reasonable level of safety, health, property protection, and public welfare by regulating the design, construction, installation, materials, location, operation, and maintenance of mechanical systems.
Permit Exemption – Portable Equipment (Section 106.2) 2018 International Mechanical Code (IMC), Section 106.2, Chapter 1
Per 2018 IMC Section 106.2, permits are not required for portable heating appliances, portable ventilation appliances and equipment, portable cooling units, or self-contained refrigeration systems containing 10 lbs or less of refrigerant or actuated by motors of 1 HP or less.
Permit Application Abandonment (Section 106.3.3) 2018 International Mechanical Code (IMC), Section 106.3.3, Chapter 1
Per 2018 IMC Section 106.3.3, a permit application is deemed abandoned 180 days after the date of filing unless pursued in good faith or a permit has been issued; extensions of additional 180-day periods may be granted by the code official.
Penalty for Commencing Work Without a Permit (Section 106.5.1) 2018 International Mechanical Code (IMC), Section 106.5.1, Chapter 1
Per 2018 IMC Section 106.5.1, any person who commences work on a mechanical system before obtaining the necessary permits shall be subject to 100 percent of the usual permit fee in addition to the required permit fees.
Emergency Permit Exception (Section 106.1 Exception) 2018 International Mechanical Code (IMC), Section 106.1 Exception, Chapter 1
Per 2018 IMC Section 106.1 Exception, where equipment or appliance replacements or repairs must be performed in an emergency situation, the permit application shall be submitted within the next working business day of the mechanical inspection department.
Successive Inspection Rule (Section 107.2.3) 2018 International Mechanical Code (IMC), Section 107.2.3, Chapter 1
Per 2018 IMC Section 107.2.3, work shall not proceed beyond the point indicated in each successive inspection without first obtaining approval of the code official, and non-compliant portions shall not be covered or concealed until authorized.
Historic Buildings Exemption (Section 102.6) 2018 International Mechanical Code (IMC), Section 102.6, Chapter 1
Per 2018 IMC Section 102.6, mandatory provisions relating to construction, alteration, repair, or restoration do not apply to buildings identified and classified as historic where the code official judges them safe and in the public interest.
Alternative Materials Approval (Section 105.2) 2018 International Mechanical Code (IMC), Section 105.2, Chapter 1
Per 2018 IMC Section 105.2, alternative materials not specifically prescribed by the code may be approved if the code official finds the design satisfactory, compliant with the intent of the code, and not less than equivalent in quality, strength, fire resistance, durability, and safety.
Reuse of Materials and Equipment (Section 105.5) 2018 International Mechanical Code (IMC), Section 105.5
Per 2018 IMC Section 105.5, materials, equipment, appliances, and devices shall not be reused unless they have been reconditioned, tested, and placed in good and proper working condition and approved; visual inspection alone is not sufficient.
Breathing Zone 2018 International Mechanical Code (IMC), Chapter 2, Section 202
The region within an occupied space between planes 3 and 72 inches above the floor and more than 2 feet from the walls of the space or from fixed air-conditioning equipment.
Standard Air 2018 International Mechanical Code (IMC), Chapter 2, Section 202
Air at a standard temperature of 70°F (21°C) and a pressure of 29.92 inches of mercury (101.3 kPa).
Modular Boiler 2018 International Mechanical Code (IMC), Chapter 2, Section 202
A steam or hot-water-heating assembly consisting of a group of individual boiler modules, each limited to a maximum input rating of 400,000 Btu/h gas, 3 gallons per hour oil, or 115 kW electric.
Conditioned Space 2018 International Mechanical Code (IMC), Chapter 2, Section 202
Per 2018 IMC Section 202, a conditioned space includes areas indirectly heated or cooled, such as spaces separated from a conditioned space by uninsulated walls, floors, or ceilings.
Ductless Mini-Split System 2018 International Mechanical Code (IMC), Chapter 2, Section 202
A heating and cooling system comprised of one or multiple indoor evaporator/air-handling units and an outdoor condensing unit connected by refrigerant piping and electrical wiring, capable of conditioning rooms without traditional ductwork.
Required Inspections (Section 107.2) 2018 International Mechanical Code (IMC), Section 107.2, Chapter 1
Per 2018 IMC Section 107.2, the three required inspections are: (1) underground inspection before backfill, (2) rough-in inspection after framing and concealed components are complete but before wall or ceiling membranes are installed, and (3) final inspection upon completion.
Undefined Terms – Where to Look (Section 201.3) 2018 International Mechanical Code (IMC), Chapter 2, Section 201.3
Per 2018 IMC Section 201.3, terms not defined in the IMC shall have meanings as defined in the International Building Code, International Fire Code, International Fuel Gas Code, or International Plumbing Code.

Formulas to Know

Permit Penalty Fee (Work Started Without Permit)Total Fee = Required Permit Fee + 100% of Usual Permit Fee
Breathing Zone Height RangeBreathing Zone = 3 inches to 72 inches above floor AND more than 2 feet from walls or fixed AC equipment
Low-Pressure Steam Boiler LimitMax Steam Pressure ≤ 15 psi (103 kPa)
Low-Pressure Hot-Water Boiler LimitsMax Water Pressure ≤ 160 psi (1103 kPa) AND Max Temperature ≤ 250°F (121°C)
Brazed vs. Soldered Joint Temperature ThresholdBrazed: alloy melting point > 1,000°F (538°C); Soldered: alloy melting point 400°F–1,000°F (204°C–538°C)
Permit Application Abandonment / Permit Expiration PeriodAbandonment or Expiration = 180 days (from filing date for application; from issue date or last work date for issued permit)
Modular Boiler Maximum Module InputMax Input per Module = 400,000 Btu/h (gas) OR 3 gal/hr (oil) OR 115 kW (electric)
Low-Heat vs. Medium-Heat Appliance Flue TemperatureLow-Heat: flue temp ≤ 1,000°F (538°C); Medium-Heat: 1,000°F < flue temp ≤ 2,000°F
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