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.
2. Apply the IRC when it is stricter than manufacturer’s instruction and apply manufacturer’s instructions when they are stricter than the IRC.

Access Requirements for Mechanical Appliances
1. Provide access to mechanical appliances that does not require removing or damaging permanent construction. Access means the ability to inspect, repair, remove, and replace the largest piece of the appliance without removing or damaging permanent construction. Permanent construction means structural materials such as studs and joists and means finish materials such as drywall and wood trim. Permanent construction includes other appliances and other piping and ducts not connected to the appliance being serviced. Example: two furnaces are located in an attic. A duct or pipe from furnace one may not block the access path or service platform for furnace two.
2. Provide a level work space or platform at least (≥) 30 inches deep and wide in front of the appliance control side, or more if recommended by the manufacturer.
3. Provide room heaters with at least (≥) 18 inches on the control side. No working platform is required in front of room heaters.

Access to Appliances Installed in Compartments, Closets, and Alcoves
1. Provide a total working space for furnaces and air handlers installed in compartments, closets, and alcoves at least (≥) 12 inches wider than the appliance and provide at least (≥) 3 inches working space on each side, back, and top of the appliance. Working space means the space required to maintain the appliance. Additional space may be required for clearance to combustible materials and for combustion air.
2. Provide at least (≥) 6 inches working space in front of the combustion chamber side of furnaces with a firebox open to the atmosphere. This includes most furnaces.
3. You are not required to apply these working space requirements to replacement appliances installed in an existing space if the appliances are installed according to manufacturer’s instructions.

Access to Appliances in Rooms where the Appliance is Not Accessible from the Service Opening
1. Provide the following access for appliances located in rooms or alcoves where the appliance is not directly accessible from the service opening: (a) a door or opening and an unobstructed passageway to the appliance that is at least (≥) 24 inches wide or large enough to remove the largest piece of appliance, whichever is greater, and (b) a level service platform at the service side of the appliance that is at least (≥) 30 inches deep and as high as the appliance or 30 inches high, whichever is greater

Access to Appliances in Attics
1. Provide the following service access for appliances located in an attic:
(a) an unobstructed finished (clear) access opening at least (≥) 22 inches by 30 inches and a continuous and unobstructed path of solid flooring at least (≥) 24 inches wide and at least (≥) 30 inches high and not more than (≤) 20 feet long measured along the center line of the floor beginning at the service opening of the appliance, and
(b) a level and unobstructed service platform at least (≥) 30 inches wide and 30 inches deep and 30 inches high on all sides of the appliance that require service access, and
(c) an opening and path that is large enough to remove the largest appliance, and
(d) a light fixture controlled by a switch located at the access opening and a receptacle near the appliance.
2. You may provide an unobstructed service access path not more than (≤) 50 feet long if the entire pathway is at least (≥) 6 feet high and at least (≥) 22 inches wide over its entire length.

Access to Appliances in Crawl Spaces
1. Provide the following service access for appliances located in a crawl space:
(a) an unobstructed finished (clear) access opening at least (≥) 22 inches by 30 inches and a continuous and unobstructed path at least (≥) 24 inches wide and at least (≥) 30 inches high and not more than (≤) 20 feet long measured along the center line of the floor beginning at the service opening of the appliance, and
(b) a level and unobstructed service area at least (≥) 30 inches wide and 30 inches deep and 30 inches high on the service side of the appliance, and
(c) an opening and path that is large enough to remove the largest appliance, and
(d) a light fixture controlled by a switch located at the access opening and a receptacle near the appliance.
2. You may provide an unobstructed service access path of unlimited length if the entire pathway is at least (≥) 6 feet high and at least (≥) 22 inches wide over its entire length.
3. Line the sides of the access path with concrete or masonry to at least (≥) 4 inches above adjoining grade if the service access path is more than (>) 12 inches below adjoining grade.
4. Provide at least (≥) 6 inches clearance between appliances suspended from the floor and soil and extend the clearance at least (≥) 12 inches on all sides of the appliance.
5. Provide a firm and level concrete pad or other approved support pad that extends at least (≥) 3 inches above the surrounding soil for appliances mounted on the ground.