A.O. Smith 197835-001 Manuel D’Utilisation

16

A sediment trap should be installed as close to the gas 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.

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 drip leg (sometimes

called a sediment trap) must be incorporated in the piping. The drip

leg 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).

Never use this water heater unless it is completely full of water. To prevent

damage to the tank, the tank must be filled with water. Water must flow

from the hot water faucet before turning “ON” gas to the water heater.

To fill the water heater with water:

1.  Close the water heater drain valve by turning the handle to the right

(clockwise). The drain valve is on the lower front of the water heater.

2.  Open  the  cold  water  supply  valve  to  the  water  heater.

3.  To insure complete filling of the tank, allow air to exit by opening the

nearest hot water faucet. Allow water to run until a constant flow is

obtained. This will let air out of the water heater and the piping.

4.  Check all water piping and connections for leaks. Repair as needed.

The first step is to determine where the vent pipe will terminate.

See Figures 19, 20, and 21. The vent may terminate through a

sidewall as shown in Figure 19 or through the roof as shown in

Figures 20 and 21.

The  vent  system  must  terminate  so  that  proper  clearances

are  maintained  as  cited  in  local  codes  or  the  current  

edition  of  the  National  Fuel  Gas  Code,  (ANSI  Z223.1,  12.9.1

through  12.9.4)  or  the  Natural  Gas  and  Propane  Installation

Code (CAN/CSA-B149.1).

Instructions on proper installation through a sidewall are provided

in Figures 15A, 15B, 15C, and 15D.

Plan  the  vent  system  layout  so  that  proper  clearances  are

maintained from plumbing and wiring.

Vent  pipes  serving  power  vented  appliances  are  classified  by

building codes as “vent connectors”. Required clearances from

combustible  materials  must  be  provided  in  accordance  with

information in this manual under FACTS TO CONSIDER ABOUT 

LOCATION and INSTALLING THE WATER HEATER, and with 

the National Fuel Gas Code and local codes.