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7. Gas Line Piping
Gas supply piping is to be sized and installed properly in order to provide a supply of
gas sufficient to meet the maximum demand without undue loss of pressure between
the meter and the boiler. Consult with the
National Fuel Gas Code ANSI Z223.1
for
proper sizing of gas piping for various lengths and diameters.
Locate a drop pipe adjacent to, but not in front of the boiler. Locate a tee in the drop
pipe at the same elevation as the gas inlet connection to the boiler. Extend the drop line
with a nipple towards the floor and cap to form a sediment trap. Install a shut off valve
before the tee with sediment trap and a union after the tee before the combination gas
valve.
When installing the boiler, make sure a pipe compound resistant to the action of
liquefied petroleum is used. Check piping for leaks. Always check leaks with a water
and soap solution.
DO NOT USE A FLAME FOR CHECKING GAS LEAKS
The boiler and its individual shut-off valve must be disconnected from the gas supply
piping during any pressure testing of that piping at test pressures in excess of 1/2 psi.
To check for gas leaks, use a
gas detector or apply a soap
solution to the joints. DO NOT
USE AN OPEN FLAME!
Manual Shutoff Valve
Height of shutoff valve above ground level to conform to
local codes, if any.
Note: Massachusetts state code requires gas shutoff to be
a tee handled gas cock.
1” X 1” X 3/4” Tee
Male Union 3/4” NPT
Burner Gas Train
Pipe Cap
3” MINIMUM
Direction of flow
Pressure Gauge Port
(1/8” NPT plugged)