User Guide

22
The water heater 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 Figure 20 and Figure 21.
SEDIMENT TRAPS
A sediment trap shall be installed as close to the inlet of
the water heater as practical at the time of water heater
installation. The sediment trap shall be either a tee
tting with a capped nipple in the bottom outlet or other
device recognized as an effective sediment trap. If a tee
tting is used, it shall be installed in conformance with
one of the methods of installation shown in Figure 20
and Figure 21.
FIGURE 20. GAS PIPING WITH FLEXIBLE CONNECTOR.
FIGURE 21. GAS PIPING WITH BLACK IRON PIPE
Contaminants in the gas lines may cause improper
operation of the gas control valve that may result in re or
explosion. Before attaching the gas line be sure that all
gas pipe is clean on the inside. To trap any dirt or foreign
material in the gas supply line, a sediment trap must be
incorporated in the piping. The sediment trap must be
readily accessible. Install in accordance with the “Gas
Piping” section. Refer to the current edition of the National
Fuel Gas Code, ANSI Z223.1/NFPA 54 or the Natural Gas and
Propane Installation Code CAN/CSA B149.1.