Specifications include, but are not limited to: Boiler shall be natural gas fired and vertical water tubed design. The boiler shall be factory-fabricated, factory-assembled, and factory-tested, water-tube boiler with heat exchanger sealed pressure tight, built on a steel base; including insulated jacket; flue-gas vent; combustion-air intake connections; water supply, return, and condensate drain connections; and controls. Heat Exchanger: The heater exchanger shall bear the ASME “H” stamp for 160 psi working pressure and shall be National Board listed. The heat exchanger shall be a “Fin Tube” design with 7/8” I.D. straight copper tubes having extruded integral fins spaced seven fins per inch. These tubes shall be “rolled” securely into glass-lined, cast iron headers. There shall be no bolts, gaskets or “O” rings in the head configuration. Removable access plugs shall be provided on the heat exchanger headers for the purposes of inspection, cleaning or repair. Burner: Natural gas, forced draft single burner premix design. The burner shall be high temperature stainless steel with a ceramic fiber outer covering to provide modulating firing rates. The burner shall be capable of a 5:1 gas train turndown without loss of combustion efficiency. The burner shall have an independent laboratory rating for Oxides of Nitrogen (NOx) to meet requirements of South Coast Air Quality Management District (SCAMD) as compliant with Rule 1146.2.
