284806-YIM-B-0707
Unitary Products Group
15
GAS CONNECTION
The gas supply line can be routed through the knock-
outs located on the front of the unit or through the
opening provided in the unit's base. Refer to Figure 13
to locate these access openings. Typical supply piping
arrangements are shown in the figures on Page 16. All
shaded items are field-supplied.
If gas supply line is routed through the unit's base
ensure that the burner assembly can be removed for
maintenance without disturbing the supply line. The
supply piping and fittings must lie below the bottom gas
manifold to avoid interference with the burner assem-
bly.
Two grommets are shipped in the blower compartment
(in parts bag taped to the blower housing) of every unit
with gas heat and should be used in the knockouts
when the gas piping penetrates the front of the unit.
After the gas supply piping has been installed, the bot-
tom opening in the unit should be sealed to prevent
water from leaking into the building.
Gas piping recommendations:
1.
A drip leg and a ground joint union must be
installed in the gas piping.
2.
When required by local codes, a manual shut-off
valve may have to be installed outside of the unit.
3.
Use wrought iron or steel pipe for all gas lines. Pipe
compound should be applied sparingly to male
threads only.
4.
All piping should be cleaned of dirt and scale by
hammering on the outside of the pipe and blowing
out the loose dirt and scale. Before initial start-up,
be sure that all of the gas lines external to the unit
have been purged of air.
5.
The gas supply should be a separate line and
installed in accordance with all safety codes as
prescribed under "Limitations". After the gas con-
nections have been completed, open the main
shut-off valve admitting normal gas pressure to the
mains. Check all joints for leaks with soap solution
or other material suitable for the purpose. NEVER
USE A FLAME.
6.
The furnace and its individual manual shut-off
valve must be disconnected from the gas supply
piping system during any pressure testing of that
system at test pressures in excess of 1/2 psig
(3.48kPa).
The furnace must 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 psig (3.48kPa).
7.
A 1/8 inch NPT plugged tap, accessible for test
gage connection, must be installed immediately
upstream of the gas supply connection to the fur-
nace.
Natural gas may contain some propane. Pro-
pane, being an excellent solvent, will quickly
dissolve white lead or most standard commer-
cial compounds. Therefore, a special pipe
compound must be applied when wrought iron
or steel pipe is used. Shellac base compounds
such as Gaskolac or Stalastic, and compounds
such as Rectorseal #5, Clyde's or John Crane
may be used.
FIRE OR EXPLOSION HAZARD
FAILURE TO FOLLOW THE SAFETY WARN-
ING EXACTLY COULD RESULT IN SERIOUS
INJURY, DEATH OR PROPERTY DAMAGE.
NEVER TEST FOR GAS LEAKS WITH AN
OPEN FLAME. USE A COMMERICALLY
AVAILABLE SOAP SOLUTION MADE SPE-
CIFICALLY FOR THE DETECTION OF
LEAKS TO CHECK ALL CONNECTIONS. A
FIRE OR EXPLOSION MAY RESULT CAUS-
ING PROPERTY DAMAGE, PERSONAL
INJURY OR LOSS OF LIFE.
