12
Figure 7. Typical Right Side Entry
Gas Service Connection.
Ground Joint
Union
Dripleg
Shut-Off Valve
with 1/8 NPT
plugged tap
Burner
Assembly
Manifold
Some utilities
require Shut-Off
Valve to be
4 to 5 feet
above floor
Automatic Gas
Valve (with manual
shut-off)
2. Lift the cap out of the unit. The cap can be pushed
up from the bottom by reaching through the fork
slot.
3. Cover the horizontal duct opening with the cap. The
insulation will be on the indoor side.
4. Fasten the cover with screws and seal to prevent
air leakage.
GAS SUPPLY AND PIPING
This unit has right side gas entry. A typical gas service
hookup is shown in
Figure 7.
When making the gas
connection, provide clearance between the gas supply line
and the entry hole in the unit’s casing to avoid unwanted
noise and/or damage to the unit.
All gas piping must be installed in compliance with local
codes and utility regulations. Some local regulations
require the installation of a manual main shut-off valve
and ground joint union external to the unit. The shut-off
valve should be readily accessible for service and/or
emergency use. Consult the local utility or gas supplier
for additional requirements regarding placement of the
manual main gas shut-off. In the absence of local codes
the gas line installation must comply with the latest edition
of the National Fuel Gas Code ANSI Z223.1 or CAN/CGA
B149 Installation Codes.
CAUTION:
Do not use matches, lighters, candles or other
sources of open fl ame to check for gas leaks.
A 1/8 inch NPT plugged tap must be installed in the gas
line immediately upstream of the gas supply connection
to the furnace for use when measuring the gas supply
pressure. The plug should be readily accessible for service
use. A drip leg should be installed in the pipe run to the
unit.
Table 4
lists gas fl ow capacities for standard pipe
sizes as a function of length in typical applications based
on nominal pressure drop in the line.
IMPORTANT NOTES:
1. Gas piping must not be run in or through air ducts,
chimneys, gas vents, elevator shafts, etc.
2. Compounds used on threaded joints of gas piping
must be resistant to the actions of liquefi ed petroleum
gases.
3. The main manual gas valve and main power
disconnect to the furnace must be properly labeled
by the installer in case emergency shutdown is
required.
Leak Check —
After the gas piping to the unit is complete,
all connections must be tested for gas leaks. To check for
leaks in gas piping systems, use only a soap and water
solution or other approved method.
IMPORTANT NOTE: When pressure testing the gas
supply lines at pressures greater than 1/2 psig (14
inches WC), the unit must be disconnected from the
gas supply piping system to prevent damage to the
gas control valve.
If the test pressure is less than or equal to 1/2 psig
(14 inches WC), the unit must be isolated from the gas
supply line by closing the manual shut-off valve.
WARNING:
This unit was equipped at the factory for use with
natural gas only. A special kit, supplied by the
manufacturer, is required to convert the unit to
operate on LP/propane gas. Failure to use the
proper conversion kit can cause fi re, explosion,
property damage, carbon monoxide poisoning,
personal injury, or death.
GAS AND HIGH ALTITUDE CONVERSIONS
Conversion: conversion of this unit must be performed by
qualifi ed service personnel, using only approved parts.
High Altitude Application
High altitude application with this furnace can be fi eld
performed by a simple adjustment of manifold pressure
and if necessary, a change of the orifi ces. The changes
