scope:

This Standard applies to newly produced, direct gas-fired make-up air heaters, hereinafter referred to as heaters, constructed entirely of new, unused parts and materials, whose purpose is to heat incoming outside air, all outside air is directly ducted to the heater and the products of combustion generated by the heater are released into the outside air stream being heated. Inside air may be added to the outside air stream after the outside air stream has passed the combustion zone.

This standard applies to theaters designed for heated air temperature rises of 15° F (83.5°F) or less and discharge air temperatures of 120 F (49°F) or less, based on inlet air temperatures of -30 F (-34.5 °c) or more.

This standard is intended to cover only complete packaged heaters, i.e., those which are designed by, cataloged by and built on a repetitive basis by the manufacturer.

This standard applies to self-contained, automatically operated heaters having integral means for air handle in which may be designed for use with ducts, discharge nozzels, grilles or louvers, and filters.

If a value for measurement as given in this standard is followed by an equivalent value in other units, the first stated value is to be regarded as the specification.