Sediment Traps; Filling The Water Heater - A.O. Smith 110 Series Instruction Manual

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 sediment trap ahead of 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.
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 should 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 should 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 gas piping to the gas control valve of water heater can be
accomplished by either of 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.

SEDIMENT TRAPS

A sediment trap should be installed as close to the inlet of the water
heater as practical at the time of water heater installation. The
sediment trap should be either a tee fitting with a capped nipple in
the bottom outlet or other device recognized as an effective sediment
trap. If a tee fitting is used, it should be installed in conformance
with one of the methods of installation shown in Figures 12 and 13.
Contaminants in the gas lines may cause improper operation of
the gas control valve that may result in fire 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).

FILLING THE WATER HEATER

18
FIGURE 14.