Williams 3501522A Owner's Manual page 8

INSTALLING YOUR FURNACE
NOTE: Minimum fresh air opening is 1 square inch
per 1,000 BTU/hr.
GAS PIPING
State and local authorities have established codes
regulating the installation of gas burning equipment.
Consult your gas supplier or gas company for complete
information. In the absence of local codes, all aspects of
the installation must comply with the National Fuel Gas
Code ANSI Z223.1. In Canada: Follow the CAN/CGA-B149.1(2)
Canadian Standard.
1. Use ½-inch pipe or semi-rigid tubing for natural
and Liquefied Petroleum Gases. DO NOT USE FLEXIBLE
HOSE. Appliance connectors of corrugated metal
tubing and fittings that are listed by a nationally
recognized testing agency may be used if accepted
by the local code authorities. FOLLOW THE
MANUFACTURER'S INSTALLATION INSTRUCTIONS.
This type of connection may only be installed in the
room where the heater is located.
2. A manual shutoff valve and union must be installed
in the gas supply line just ahead of the connection to
the heater. The manual valve must include a 1/8-inch
NPT plugged tapping accessible for connection of a
test gauge.
3. Unions in the gas supply lines should be of the ground
joint type. Compounds used on threaded pipe joints
must be resistant to the action of liquefied petroleum
gases.
WARNING: When connecting field piping,
use a second wrench to keep the heater valve from
turning. Support field piping properly, stress and over
tightening could damage the gas valve and result
in dangerous gas leaks which can cause dangerous
conditions including property damage, bodily injury,
and even death.
4. A drip leg Figure 2 should be installed to constitute a
trap to catch any condensate that may be in the gas.
The drip leg should be readily accessible for cleaning.
5. The heater must be disconnected from the gas supply
system and from the heaters individual shutoff valve
when the system is tested at a pressure in excess of
1/2 PSI.
6. Check all factory and field pipe joints for gas leaks
before and after lighting the heater. Use a soap solution.
Never use a match or open flame. Correct any leak(s),
no matter how small.
7. Piping supply shall be supported to prevent sagging
damage to the controls and hazardous gas leaks. To
prevent freezing where the supply pipe is exposed to
cold air, wrap the pipe or run it underground.
8
VENTED ROOM HEATERS
FIGURE 2 - LEFT SIDE GAS INLET
FIGURE 3 – PROPER PIPING PRACTICE
PROPER PIPE
THREADING
INCORRECT
THREADING
OVER-THREADED
IMPORTANT: All piping must comply with local codes and
ordinances or with the National Fuel Gas Code (ANSI Z223.1
NFPA No. 54), whichever applies. (In Canada: CAN/CGA B149).
2 THREADS EXPOSED
SEALANT THIN
ENOUGH TO SHOW
THREADS
DAMAGED
SEALANT
THREADS
PAST TIP
SEALANT
TOO THICK