1.1 SCOPe 1.1.1 This standard applies to newly produced pool heaters (see Part IV,
Definitions), hereinafter referred to as pool heaters or appliances,
constructed entirely of new, unused parts and materials, for heating
nonpotable water stored at atmospheric pressure, such as water in
swimming pools, spas, hot tubs and similar applications: a. For use with natural gas; b. For use with manufactured gas; c. For use with mixed gas; d. For use with liquefied petroleum gases; and e. For use with LP gas-air mixtures. 1.1.2 This standard also applies to pool heaters intended for installation at
a distance less than 5 feet (1.52 m) from the inside surface of a pool
or spa, hereinafter referred to as close proximity heaters (see Part
IV, Definitions). 1.1.3 This standard also applies to pool heaters for indoor installation with
draft hoods which are factory equipped with automatic vent damper
devices (see Part IV, Definitions), hereinafter referred to as vent
damper devices. 1.1.4 This standard also applies to pool heaters of other than the direct
vent type which are factory equipped with electrically operated or
mechanically actuated automatic flue damper devices (see Part IV,
Definitions), hereinafter referred to as flue damper devices. 1.1.5 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. 1.1.6 All references to psi throughout this standard are to be considered
gage pressure unless otherwise specified. 1.1.7 Exhibit D contains provisions that are unique to the United States. 1.1.8 Exhibit E contains provisions that are unique to Canada. 1.1.9 Special construction provisions applicable to a water heater designed
for use with an optional listed conversion kit are outlined under
Exhibit F (Optional Provisions of Listed Gas Appliance Conversion
Kits.) 1.1.10 Exhibit G contains a list of standards referenced in this standard, and
sources from which these reference standards may be obtained.