HEATING / COOLING

Access to Mechanical Appliances

APPLICATION OF CHAPTER PROVISIONS

1. Apply the provisions of this chapter to heating and cooling equipment that is not covered in other chapters. This means you should apply this chapter unless something in another chapter specifically addresses or contradicts this chapter. This chapter covers general installation requirements for central heating and cooling equipment and for water heaters. See Chapters 14 and 18 for specific requirements covering appliances such as oil-fired furnaces, heat pumps, and electric heaters. See Chapters 20 and 28 for additional water heater requirements. See Chapter 24 for additional requirements for gas-fired appliances.
Read the full Topic

Adding or Removing Liquid and Solid-Fuel Appliances From Chimneys and Vents

Description of Potential Problems when Adding or Removing Fuel-Burning Appliances
Every fuel-burning appliance has diff erent characteristics that will aff ect the operation of a chimney or vent. Adding or removing appliances may cause a chimney or vent that once operated properly to operate improperly. Problems that may occur include backdrafting of exhaust gasses into the home and condensation of moisture that can quickly damage the chimney or vent. Backdrafting and damaged chimneys and vents are a signifi cant safety hazard. Read the full Topic

Air Conditioning Condensate Disposal

Condensate Description
The process of removing heat from the air is often called air conditioning. Water is a byproduct of air conditioning because water vapor condenses out from the air when the air temperature is reduced. In areas with high humidity, air conditioning can produce signifi cant amounts of water. The water removed from the air during air conditioning is called condensate. Read the full Topic

Appliance Installation, Anchorage, Elevation, and Protection

Appliances Governed by these Code Provisions                                                                                                                                                                                                                                                1. Apply these code provisions to all fuel-burning mechanical appliances including appliances using natural and propane gas, oil, and solid fuels.
Read the full Topic

Chimneys and Vents for Liquid and Solid-Fuel Appliances

APPLIANCES GOVERNED BY THIS CHAPTER
1. Apply the provisions in this chapter to chimneys and vents used by solid and liquid-fuel burning mechanical appliances. The most common modern appliances governed by this chapter are oil-burning appliances such as boilers and furnaces. Do not apply these requirements to fireplaces. Refer to Chapter 10 for information about fi replace chimneys. Do not apply these requirements to gas-burning appliances. Note that similar provisions for gas appliances begin at IRC Chapter 24. Read the full Topic

Combustion Air

This chapter was effectively deleted in IRC 2009.

Refer to manufacturer’s instructions when providing combustion air for solid-fuel-burning appliances. Read the full Topic

Connection of Vent Connectors to Chimneys for Liquid and Solid Fuel Appliances

Liquid and Solid-Fuel Vent Connector Material
1. Use at least (≥) 26 gage galvanized sheet metal for any single-wall vent connectors less than (<) 6 inches diameter.
2. Use at least (≥) 24 gage galvanized sheet metal for any single wall vent connectors at least (≥) 6 inches and not more than (≤) 10 inches diameter. Read the full Topic

Coolant Access Caps

1. Install locking-type, tamper-resistant caps on refrigerant line access ports located outdoors or provide another approved means to prevent unauthorized access.

Draft Hoods, Draft Regulators, and Dampers for Liquid and Solid Fuel Appliances

Draft Hood Location
1. Locate an appliance’s draft hood in the same room or space where the combustion air openings are located. Read the full Topic

Duct System Design

1. Design all ducts that serve heating, cooling, and ventilation appliances using Air Conditioning Council of America (ACCA) Manual D or another approved method.

Electric Heating Elements Installed in HVAC Ducts, Heat Pumps, and Air Conditioners

Electric Heating Element Description                                                                                                                                                                                                                                                                        Electric resistance heating elements are often installed in heat pumps when they are used cold climates. These supplemental electric heating elements activate if the temperature becomes too cold for the heat pump to provide adequate heat. These elements become very hot and proper installation is important to prevent fires and electrical problems. Read the full Topic

Electric Radiant Heating Systems Installation Requirements

Electric Radiant Heating Description
Electric radiant heating systems provide heat to a single room. They usually have no fan and provide heat by natural movement of the heated air and by thermal radiation. They are common in small seasonally occupied buildings, some rural homes, and in buildings without ducts for forced-air heating and cooling. These elements become very hot and proper installation is important to prevent fi res and electrical problems. Read the full Topic

Evaporative Cooling Appliances Installation Requirements

Evaporative Cooling Appliances Description
Evaporative coolers (also called swamp coolers) are usually located on the roof or on the ground outside the home. They work by running a stream of water over one or more media that look similar to a sponge. A fan draws air through the media and the evaporation of the water lowers the air temperature. The fan blows this cooled air through ducts into the home. Evaporative coolers work only in dry areas of the country and are most effective when the dew point is less than about 55º F.

Read the full Topic

Factory Built Fireplaces and Chimneys

Factory-Built Fireplace and Chimney Discussion                                                                                                                                                                                                                                     Factory-built fireplaces and chimneys include components tested, listed, and labeled to be installed together as a system. Such fireplaces are usually designed to burn solid fuels, such as wood, although they may be converted to use gas logs if approved by the fireplace manufacturer. Do not mix components from different manufacturers unless approved by the fireplace manufacturer. Fireplaces designed to burn only gas are not really fireplaces. They are decorative gas appliances. Vented decorative gas appliances are more like a water heater than like a fireplace. Unvented decorative gas appliances are more like a gas range than like a fireplace. Install and use decorative gas appliances according to manufacturer’s instructions and IRC Chapter 24. Note that some jurisdictions do not allow unvented decorative gas appliances. Also note that manufacturers of unvented decorative gas appliances recommend opening a window during use and recommend limits on the duration of use. Read the full Topic

Fireplace Combustion Air

Combustion Air Required

1. Provide combustion air from outside the building for masonry and factory-built fireplaces.

Read the full Topic

Flexible Duct Installation

General Installation Requirements
1. Install flexible ducts according to manufacturer’s installation instructions. The installation instructions that follow are from the Air Diffusion Council and may be downloaded at www.flexibleduct.org.
2. Use flexible ducts that are labeled at least (≥) every 36 inches with information such as the manufacturer’s name and the R-value of the duct insulation. Read the full Topic

Framing Cavity Return Ducts

Return Ducts in Framing Cavities Installation Requirements
1. You may use framing cavities in interior areas, such as cavities in interior stud wall and between solid floor joists, as return ducts or plenums. Do not use framing cavities for supply ducts or plenums. Consult your local building official to reconcile this provision with IRC provision N1102.2.10. Read the full Topic

Hot Water and Steam Boilers

Labeling and Instructions Requirements
1. Attach to the boiler a permanent and complete set of operating instructions, rating data, and the manufacturer’s nameplate.
2. Provide a complete control diagram and complete operating instructions when the boiler is installed. Read the full Topic

HVAC Appliances General Installation Requirements

Appliances Installation by Manufacturer’s Instructions
1. Install heating and cooling equipment and appliances according to manufacturer’s installation instructions and provisions of the IRC.
Read the full Topic

Masonry Chimneys

Chimney Termination Height                                                                                                                                                                                                                                                                                       

1. Terminate a masonry chimney at least (≥) 3 feet above the roof and at least (≥) 2 feet above any part of the building within 10 feet of the chimney. Measure termination height above the roof from the highest point where the chimney penetrates the roof to where the flue exits the chimney. This provision also applies to many factory-built chimneys. Confirm factory-built chimney termination height using the manufacturer’s installation instructions.

Read the full Topic

Masonry Fireplaces

Components Governed by this Chapter                                                                                                                                                                                                                                                            

The material in this chapter applies to masonry chimneys and fireplaces unless otherwise indicated. For rules governing factory-built fireplaces and chimneys, refer to sections of this chapter that specifically address factory-built chimneys and fireplaces and to the manufacturer’s instructions for those components. If there is a diff erence between manufacturer’s instructions and code provisions, use the manufacturer’s instructions unless the IRC specifically states that you should use code provisions.

Read the full Topic

Mechanical Systems Changes and Maintenance

Mechanical Systems Governed by the IRC                                                                                                                                                                                                                                                                  

Mechanical systems governed by the IRC are permanently installed heating, ventilation, and air conditioning systems. The IRC does not govern temporary and portable appliances and it does not govern most plug-and-cord connected heating and cooling appliances. HVAC is a common acronym that refers to mechanical systems and stands for heating, ventilation, and air conditioning. Read the full Topic

Oil and Solid-Fuel Appliance Clearance Reduction to Combustible Materials

Appliances Governed by these Code Provisions                                                                                                                                                                                                                                                 1. Apply these clearances to combustible reduction provisions to oil and solid fuel-burning appliances and apply these provisions to related appliances such as vents and chimneys.
Read the full Topic

Outdoor and Retuen Air Location and Installation

Appliances Governed by these Code Provisions
1. Apply these code provisions to forced-air furnaces, and to air conditioning systems, and to heat pumps. Read the full Topic

Pool Heater Installation

Pool Heater General Installation Requirements
1. Install pool heaters according to the manufacturer’s instructions and applicable IRC provisions. If a conflict exists between the manufacturer’s instructions and the IRC, the more restrictive provision applies. Read the full Topic

Underground Ducts

Ducts Installed Underground or in Concrete
1. Use approved concrete, clay, metal, or plastic for HVAC ducts that are installed underground or in concrete.
2. Protect metal ducts from corrosion or completely surround them with concrete at least (≥) 2 inches thick. Read the full Topic

Vented Floor Furnaces

Vented Floor Furnace Description
Vented floor furnaces provide heat to a single room or a small home with a few rooms. If they have no fan, they provide heat by natural movement of the heated air and by thermal radiation. They are most common in small seasonally occupied buildings and some rural homes. These furnaces become very hot and proper installation is important to prevent fires. Read the full Topic

Vented Room Heaters

Vented Room Heater Description
Vented room heaters provide heat to a single room or adjacent rooms. If they have no fan, they provide heat by natural movement of the heated air and by thermal radiation. They are most common in small seasonally occupied buildings, room additions, and homes in warm climates where heating demand is minimal and occasional. These heaters become very hot and proper installation is important to prevent fi res and electrical problems. Read the full Topic

Vented Wall Furnaces

Vented Wall Furnace Description
Vented wall furnaces provide heat to a single room or adjacent rooms. If they have no fan, they provide heat by natural movement of the heated air and by thermal radiation. They are most common in small seasonally occupied buildings, room additions, and homes in warm climates where heating demand is minimal and occasional. These furnaces become very hot and proper installation is important to prevent fires. Read the full Topic

Vents for Liquid and Solid Fuel Appliances

Appliances Governed by these Code Provisions
1. Apply these code provisions to vents (not chimneys) used by liquid and solid-fuel-burning appliances.
2. Do not apply these code provisions to direct vent appliances. Read the full Topic

Water Heater and Installation Access

Water Heater General Installation Requirements
1. Install water heaters according to the manufacturer’s instructions and applicable IRC provisions. Refer to Chapter 13 for water heater seismic strapping requirements.
2. Provide access to water heaters for service and replacement. Refer to Chapter 13. Read the full Topic

Water Heater Drip Pans and Relief Valves

Water Heater Drip Pan Requirements
1. Install a drip pan under storage tank water heaters located where leakage could cause damage. The IRC does not specify these locations. They often include attics and all areas within the conditioned area of the home, including finished basements. This provision does not apply to demand type (tankless) water heaters. Read the full Topic