PV 6126b 6/01
1
SPECIFICATION FOR DOMESTIC WATER HEATERS
Atmospheric Combustion, Gas-Fired Water Heaters
with Nickel-Plated Storage Tanks
Furnish and install atmospheric gas water heater(s) as manufactured by PVI Industries, L.L.C.
of Fort Worth, Texas. Supply quantities and model numbers as indicated on the plumbing schedule.
Gas and Electrical Consumption
The water heater will operate at 80% thermal efficiency. The water heater will comply with paragraph 7.2.4.4, the
thermal efficiency, the standby loss, and all other requirements of ASHRAE 90.1-1999.
Pressure Vessel and Heating Surfaces
The water heater will be a vertical fire tube design that is constructed and stamped in accordance with Section IV,
Part HLW of the ASME code. Both the storage and heating sections of the water heater will be National Board
Registered for a working pressure of 150 psi and will be pressure tested at 1-1/2 times working pressure. The fireside of
the heating surfaces will be of boiler-grade steel. The waterside of the heating tubes will be sealed in copper. The
heating tubes will be rolled, beaded, and seal welded into the tube sheets. The combustion side of the tube sheet will be
insulated by a layer of ceramic fiber that will protect the tube sheet from both thermal stresses and failure that can result
from the accumulation of scale and precipitants.
Tank Lining
The tank will be a plated with electroless nickel (EN). Plating will occur after the pressure vessel is completely
fabricated and all welding is completed. The EN plating will be a high-phosphorus (10%) and nonporous composition
suitable for submersion service (ASTM B733 standard may be used as a guideline). The finished lining will not require
sacrificial anode rods. For additional protection against galvanic corrosion, which may occur within the potable water
system, the EN plating may have a high-dielectric-strength polymer overcoat.
Burner and Venting
Combustion will be provided by an atmospheric burner with a gas train meeting the following agency requirement for
the input specified:
___ UL (standard)
____ FM
___ IRI
___ Other ______________________
Water heater will be a category 1, non-condensing appliance. It will be UL-listed for use with non-pressurized, type
B venting material.
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