This publication represents a basic standard for safe operation, substantial and durable construction, and acceptable performance of gas-fired central furnaces. It is the result of years of experience in the manufacture, testing, installation, maintenance, inspection and research on gas-fired central furnaces designed for utilization of gas. There are risks of injury to persons inherent in appliances that, if completely eliminated, would defeat the utility of the appliance. The provisions in this standard are intended to help reduce such risks while retaining the normal operation of the appliance.
This Standard applies to automatically operating gas-fired central furnaces see Part XI, Definitions, hereinafter referred to as furnaces, for installation in residential, commercial, and industrial structures including furnaces for Direct Vent, Recreational Vehicle, Outdoor, and Manufactured (Mobile) Homes. These furnaces may include a cooling unit. All units shall be constructed entirely of new, unused parts and materials.