Idaho HVAC Journeyman Exam

Key Concepts

Scope (Section 101.2). The IMC regulates the design, installation, maintenance, alteration and inspection of permanently installed mechanical systems used to control environmental conditions and related processes within buildings, plus the systems, components, equipment and appliances specifically addressed in the code. Fuel gas distribution piping and equipment, fuel gas-fired appliances and fuel gas-fired appliance venting systems are regulated by the International Fuel Gas Code, not the IMC.

Residential exception (Section 101.2 Exception). Detached one- and two-family dwellings and multiple single-family dwellings (townhouses) not more than three stories high with separate means of egress, and their accessory structures, comply with the International Residential Code.

Key Concepts

How definitions are applied (Section 201) - Unless otherwise expressly stated, the words and terms of the code have the meanings given in Chapter 2 (Section 201.1). - Present tense includes the future; masculine includes feminine and neuter; singular includes plural and plural includes singular (Section 201.2). - Where terms are not defined in the IMC but are defined in the International Building Code, International Fire Code, International Fuel Gas Code or International Plumbing Code, those codes' meanings apply (Section 201.3). In Idaho, references to the IPC are construed as referring to the Idaho State Plumbing Code (UpCodes note, IDAPA 24.39.70). - Where a term is not defined through the authorized methods, it "shall have ordinarily accepted…

Key Concepts

Prohibited and restricted locations - Fuel-fired appliances shall not be located in sleeping rooms (Section 303.3). Exceptions exist for direct-vent appliances that obtain all combustion air directly from the outdoors, solid fuel-fired appliances with proper combustion air, and appliances in dedicated enclosures with outdoor combustion air — so any statement that they are permitted "without any exceptions" is false. - Fuel-fired appliances shall not obtain combustion air from bathrooms (among other prohibited spaces) (Section 303.3). - Furnaces installed in closets shall be listed for such installation (Section 303.5). - Mechanical systems shall not be located in an elevator shaft (Section 303.8).

Key Concepts

• Ventilation required (401.2): Every occupied space must be ventilated by natural means per Section 402 or mechanical means per Section 403. Where a dwelling unit's air infiltration rate is less than 5 air changes per hour when blower-door tested at 0.2-inch water column per IECC Section R402.4.1.2, the unit must be ventilated mechanically per Section 403. Ambulatory care facilities and Group I-2 occupancies follow Section 407 (ASHRAE 170, per 407.1). Ventilation is provided during occupied periods (401.3).
• Intake opening location (401.4): Intakes not less than 10 feet from lot lines or buildings on the same lot (Item 1); not less than 10 feet horizontally from any hazardous or noxious contaminant source such as vents, streets,…

Study Brief

Key Concepts

Exhaust discharge and separation distances (Section 501.3, 501.3.1, 501.3.2) - Exhaust air must discharge outdoors where it will not cause a public nuisance and cannot be readily drawn back in by a ventilating system. Air shall not be exhausted into an attic, crawl space, or directed onto walkways (Section 501.3). - Ducts conveying explosive or flammable vapors, fumes or dusts: 30 ft from property lines; 10 ft from operable openings into buildings; 6 ft from exterior walls and roofs; 30 ft from combustible walls and operable openings that are in the direction of the exhaust discharge; 10 ft above adjoining grade (Section 501.3.1, Item 1). - Other product-conveying outlets: 10 ft from property lines; 3…

Idaho HVAC Journeyman Exam

Key Concepts

Return air openings (Section 601.5). Return air openings must comply with all of the following: openings shall not be located less than 10 feet (3048 mm) measured in any direction from an open combustion chamber or draft hood of another appliance in the same room or space (Item 1); return air shall not be taken from a hazardous or insanitary location or a refrigeration room (Item 2); the amount of return air from any room shall be not greater than the supply air delivered to that space (Item 3); return and transfer openings shall be sized per the manufacturer's installation instructions, ACCA Manual D, or the design of the registered design professional (Item…

Idaho HVAC Journeyman Exam — 2018 IMC Chapter 8: Chimneys and Vents

Key Concepts

Scope and general venting (Section 801.1, 801.2) — Chapter 8 governs installation, maintenance, repair and approval of factory-built chimneys, chimney liners, vents and connectors, and the utilization of masonry chimneys. Gas-fired appliances are vented per the International Fuel Gas Code. Every fuel-burning appliance must discharge products of combustion to a vent, factory-built chimney or masonry chimney, except appliances vented per Section 804. Oil-fired appliances are vented in accordance with this code and NFPA 31 (Section 801.2.1).

Idaho HVAC Journeyman Exam

Key Concepts

Scope and general limits - Chapter 9 governs approval, design, installation, construction, maintenance, alteration and repair of the appliances and equipment identified in it, plus factory-built fireplaces; gas-fired appliances are regulated by the International Fuel Gas Code (Section 901.1). - Fireplaces and solid fuel-burning appliances shall not be installed in hazardous locations (Section 901.3). In Group I-2, Condition 2 occupancies, solid fuel-burning fireplaces and appliances are prohibited (Section 901.4).

Cooling towers, evaporative condensers and fluid coolers (Section 908) - Located to prevent discharge vapor plumes from entering occupied spaces; plume discharges shall be not less than 5 feet (1524 mm) above or 20 feet (6096 mm) away from any ventilation inlet to a…

Idaho HVAC Journeyman Exam

Key Concepts

Scope (Section 1001.1). Chapter 10 governs the installation, alteration and repair of boilers, water heaters and pressure vessels. Exceptions include pressure vessels for unheated water supply; portable unfired pressure vessels and ICC containers; bulk oxygen and medical gas containers; unfired pressure vessels of 5 cubic feet or less operating at pressures not exceeding 250 psi in Groups B, F, H, M, R, S and U; refrigeration pressure vessels regulated by Chapter 11; pressure tanks used with coaxial/telephone/power cables; and any boiler or pressure vessel subject to federal or state inspection.

Idaho HVAC Journeyman Exam

Key Concepts

Scope and referenced standards - Chapter 11 governs the design, installation, construction and repair of refrigeration systems that vaporize and liquefy a fluid during the refrigerating cycle (Section 1101.1). - Refrigeration systems shall comply with this code and, except as modified, ASHRAE 15. Ammonia systems shall also comply with IIAR 2, IIAR 3, IIAR 4 and IIAR 5 (Section 1101.6). - Pressure vessels used in refrigeration systems regulated by Chapter 11 are excepted from Chapter 10 (Section 1001.1, Exception 5).

Idaho HVAC Journeyman Exam

Key Concepts

Scope and alternative standard - Chapter 12 governs construction, installation, alteration and repair of hydronic piping that is part of HVAC systems, including steam, hot water, chilled water, steam condensate and ground-source heat pump loop systems (Section 1201.1). - As an alternative to Sections 1202 and 1203, piping may be designed, installed, inspected and tested in accordance with ASME B31.9 (Section 1201.3).

Materials - Hydronic pipe shall conform to the standards in Table 1202.4; the exterior of the pipe shall be protected from corrosion and degradation (Section 1202.4). - Pipe fittings shall conform to the respective pipe standards or to Table 1202.5 (Section 1202.5). - General hydronic: reused pipe, fittings, valves or other…

Idaho HVAC Journeyman Exam

Key Concepts

Scope and general requirements - Chapter 13 governs the design, installation, construction and repair of fuel-oil storage and piping systems (Section 1301.1). - An appliance shall be designed for use with the type of fuel to which it will be connected, and shall not be converted from the fuel on the rating plate without reapproval from the code official (Section 1301.3). - Where an oil burner is served by a tank, any part of which is above the level of the burner inlet connection, and the fuel supply line is taken from the top of the tank, an approved antisiphon valve or other siphon-breaking device shall be installed in lieu of the shutoff…

Idaho HVAC Journeyman Exam

Key Concepts

Scope (Section 1401.1). Chapter 14 governs the design, construction, installation, alteration and repair of solar thermal systems, equipment and appliances intended to use solar energy for space heating or cooling, domestic hot water heating, swimming pool heating or process heating. Per the chapter's user note, Chapter 14 addresses solar thermal systems, not photovoltaic systems.

Listing and labeling (Sections 1401.4, 1402.1). Solar thermal systems shall be listed and labeled in accordance with ICC 900/SRCC 300 and installed per the manufacturer's instructions and ICC 900/SRCC 300. Collectors and panels shall be listed and labeled in accordance with ICC 901/SRCC 100 (Sections 1401.4.1, 1402.8.1.1).

Key Concepts

Scope and pressure limits - The code applies to installation of fuel-gas piping systems, fuel gas appliances, gaseous hydrogen systems and related accessories (Section 101.2). Exception: detached one- and two-family dwellings and multiple single-family dwellings (townhouses) not more than three stories high with separate means of egress, and their accessory structures, comply with the International Residential Code. - Piping systems covered: natural gas at an operating pressure of 125 psig (862 kPa gauge) or less, and LP-gas at 20 psig (140 kPa gauge) or less, except as provided in Section 402.7 (Section 101.2.2). Coverage extends from the point of delivery to the outlet of the appliance shutoff valves. - Gaseous hydrogen systems are regulated by Chapter 7…

Key Concepts

How Chapter 2 works. Section 201.1 (Scope) states that unless otherwise expressly stated, the words and terms in this chapter carry the meanings indicated there "for the purposes of this code and standard." Section 201.2 (Interchangeability) provides that the present tense includes the future, masculine includes feminine and neuter, and singular includes plural (and vice versa). Section 201.3 (Terms Defined in Other Codes) sends you to the International Building Code, International Fire Code, International Mechanical Code or International Plumbing Code for terms not defined in the IFGC — and the Idaho note (IDAPA 24.39.70) states that all references to the IPC are construed as referring to the Idaho State Plumbing Code. Section 201.4 (Terms Not Defined) gives…

Idaho HVAC Journeyman Exam — General Regulations

Key Concepts

Listing, labeling and nameplates - Appliances shall be listed and labeled for the application in which they are used unless otherwise approved under Section 105 (Section 301.3). - The permanent factory-applied nameplate must show the manufacturer's name or trademark, model number, serial number, the seal or mark of the testing agency (listed appliances), the hourly rating in Btu/h, the type of fuel approved, and the minimum clearance requirements (Section 301.5).

Prohibited and restricted locations - Appliances, equipment and systems regulated by the code shall not be located in an elevator shaft — no exception for listed and labeled equipment (Section 301.15). - No appliances in sleeping rooms, bathrooms, toilet rooms,…

Key Concepts

Scope and general requirements (Section 401) - The chapter governs piping from the point of delivery to the appliance connections, including design, materials, fabrication, testing and maintenance (401.1). Utility service piping inside buildings follows the structural safety and fire protection provisions of the International Building Code (401.1.1). - LP-gas storage systems shall be designed and installed per the International Fire Code and NFPA 58 (401.2). - Additional appliances: the existing piping must be checked for adequate capacity for all appliances served; if inadequate, the existing system shall be enlarged as required or separate piping of adequate capacity shall be provided (401.4). - Identification: for other than steel pipe, exposed piping shall carry a **yellow label marked "Gas"…

Idaho Fuel Gas Code 2018 — Chapter 5 Chimneys and Vents

Key Concepts

Venting required / not required - Every appliance shall discharge products of combustion outdoors, except appliances exempted by Section 501.8 (Section 501.2). - Appliances not required to be vented include ranges (Item 1), built-in domestic cooking units listed for optional venting, hot plates and laundry stoves, Type 1 clothes dryers, refrigerators, counter appliances, room heaters listed for unvented use, direct-fired makeup air heaters, and specialized appliances of limited input (Section 501.8). - Where appliances in Items 5 through 11 aggregate more than 20 Btu per hour per cubic foot of room volume, one or more must be vented so the remaining unvented appliances do not exceed…

Idaho HVAC Journeyman Exam

Key Concepts

Unvented Room Heaters (Section 621) - Tested to ANSI Z21.11.2 (§621.1). - One or more unvented room heaters shall not be used as the sole source of comfort heating in a dwelling unit (§621.2). - Maximum input rating: 40,000 Btu/h (11.7 kW) (§621.3). - Prohibited within occupancies in Groups A, E and I (§621.4). - Aggregate input of all unvented appliances in a room or space: not more than 20 Btu/h per cubic foot of volume. Adjoining rooms connected by a doorway, archway or comparable opening that cannot be closed may be included in the volume calculation (§621.5). - Must have an oxygen-depletion-sensitive safety shutoff system that shuts off gas to main and…

Idaho HVAC Journeyman Exam

Key Concepts

Scope and definitions (Sections 701.1, 702.1) - Installation of gaseous hydrogen systems shall comply with Chapter 7 and Chapters 53 and 58 of the International Fire Code; compressed gases also comply with Chapter 50 of the IFC (701.1). - A gaseous hydrogen system is an assembly of piping, devices and apparatus designed to generate, store, contain, distribute or transport a nontoxic, gaseous hydrogen containing mixture having at least 95-percent hydrogen gas by volume and not more than 1-percent oxygen by volume (702.1). - A hydrogen fuel-gas room is a room or space intended exclusively to house a gaseous hydrogen system (702.1).