Installation Guide
34
The gas piping may enter the left or right side of the furnace
cabinet. The installer must supply rigid pipe long enough to reach
the outside of the cabinet to seal the grommet cabinet penetra-
tion. A semi-rigid connector to the gas piping can be used outside
the cabinet per local codes. 1/2” NPT pipe and fittings are re-
quired. For models with an “L” shaped manifold, a 4 1/2”
long nipple is required. For models with a hook shaped manifold, a 2” long nipple is required.
From the elbow, the length of pipe and the fittings required will vary by the side chosen, location of union and cabinet width.
The union may be placed inside or outside of the cabinet.
GAS PIPING CHECKS
Before placing unit in operation, leak test the unit and gas connec-
tions.
Check for leaks using an approved chloride-free soap and water
solution, an electronic combustible gas detector, or other approved
testing methods.
NOTE: Never exceed specified pressures for testing. Higher pressure may damage the gas valve and cause subsequent overfiring,
resulting in heat exchanger failure.
Disconnect this unit and shutoff valve from the gas supply piping system before pressure testing the supply piping system with
pressures in excess of 1/2 psig (3.48 kPa).
Isolate this unit from the gas supply piping system by closing its external manual gas shutoff valve before pressure testing supply
piping system with test pressures equal to or less than 1/2 psig (3.48 kPA).
Manual Shut Off Valve
(upstream from
ground joint
pipe union)
When gas line is in the alternate location, swap the position
of the plug and grommet.
UPFLOW - HORIZONTAL LEFT
Figure 37
Drip Leg
Plug in Main Gas Line Hole
Alternate
Union
Location
Manual Shut Off Valve
(upstream from
ground joint pipe union)
Gas
Valve
Burners
Drain Trap
Manifold
Plug in Alternate Gas Line Hole
Grommet in
Standard Gas Line Hole
Drip leg may terminate with a 1/2” x 1/8” pipe plug to accommodate
line gas pressure measurement.
COUNTERFLOW - HORIZONTAL RIGHT
Figure 38
E
DGES
OF
SHEET
METAL
HOLES
MAY
BE
SHARP
. U
SE
GLOVES
AS
A
PRECAUTION
WHEN
REMOVING
HOLE
PLUGS
.
WARNING
T
O
AVOID
THE
POSSIBILITY
OF
EXPLOSION
OR
FIRE
,
NEVER
USE
A
MATCH
OR
OPEN
FLAME
TO
TEST
FOR
LEAKS
.
WARNING