Gas Piping - A.O. Smith ARGSS02708 Instruction Manual

GAS PIPING

Make sure the gas supplied is the same type listed on the model rating
plate. The inlet gas pressure must not exceed 14 inch water column (3.5
kPa) for natural and propane gas (L.P.). The minimum inlet gas pressure
shown on the rating plate is that which will permit firing at rated input.
All gas piping must comply with local codes and ordinances or with the
National Fuel Gas Code (ANSI Z223.1/ NFPA-54) or the Natural Gas and
Propane Installation Code (CAN/CSA B149.1) whichever applies. Copper
or brass tubing and fittings (except tin lined copper tubing) shall not be used.
If the gas control valve is subjected to pressures exceeding 1/2 psi
(3.5 kPa), the damage to the gas control valve could result in a fire
or explosion from leaking gas.
If the main gas line Shut-off serving all gas appliances is used, also
turn "off" the gas at each appliance. Leave all gas appliances shut
"off" until the water heater installation is complete.
A gas line of sufficient size must be run to the water heater. Consult
the current edition of National Fuel Gas Code (ANSI Z223.1/NFPA
54) or the Natural Gas and Propane Installation Code (CAN/CSA
B149.1) and your gas supplier concerning pipe size.
There must be:
• A readily accessible manual shut off valve in the gas supply line
serving the water heater, and
• A drip leg (sediment trap) ahead of the gas control valve to help
prevent dirt and foreign materials from entering the gas control valve.
• A flexible gas connector or a ground joint union between the shut
off valve and control valve to permit servicing of the unit.
Be sure to check all the gas piping for leaks before lighting the water
heater. Use a soapy water solution, not a match or open flame.
Rinse off soapy solution and wipe dry.
This heater is approved for operation up to 5,300 feet (1,615 m) without
alteration. High altitude models are available from the factory for elevations
between 5,300 feet (1,615 m) and 10,100 feet (3,079 m). For elevations
above 10,100 feet (3,079 m) the input rating should be reduced at the rate of
4 percent for each 1,000 feet (305 meters) above sea level which requires
replacement of the burner orifice in accordance with National Fuel Gas Code
(ANSI Z223.1/NFPA 54) or the Natural Gas and Propane Installation Code
(CAN/CSA B149.1). Contact your local gas supplier for further information.
Failure to replace the standard orifice with a high altitude orifice when
installed above 10,100 feet (3,079 m) could result in improper and inefficient
operation of the appliance, producing carbon monoxide gas in excess of
safe limits, which could result in serious injury or death. Contact your gas
supplier for any specific changes which may be required in your area.
Use pipe joint compound or teflon tape marked as being resistant to
the action of petroleum [Propane (L.P.)] gases.
The appliance and its gas connection must be leak tested before
placing the appliance in operation.
The appliance and its individual Shut-off valve shall be disconnected from
the gas supply piping system during any pressure testing of that system at
test pressures in excess of 1/2 pound per square inch (3.5 kPa). It shall be
isolated from the gas supply piping system by closing its individual manual
Shut-off valve during any pressure testing of the gas supply piping system
at test pressures equal to or less than 1/2 pound per square inch (3.5 kPa).
Connecting the gas piping to the gas control valve of the water heater can
be accomplished by either of the two methods shown in Figures 12 and 13.
FIGURE 12. GAS PIPING WITH
FLEXIBLE CONNECTOR.
FIGURE 13. GAS PIPING WITH ALL
BLACK IRON PIPE TO GAS CONTROL.
14