Gas Piping - Lennox G21Q Series Installation Instructions Manual

Front View
INTAKE
AIR
5
(127)
EXHAUST
AIR
INTAKE
AIR
VENT TERMINATIONS
MODEL WTK WALL TERMINATION KIT (30G28)
EXTENDED VENT FOR GRADE CLEARANCE
FIGURE 16
Front View
INTAKE
34
(864)
4
Side View
(102)
VENT TERMINATIONS
MODEL WTKX (30G79)
EXTENSION RISER FOR GRADE CLEARANCE
FIGURE 17
COVER EXHAUST
12
(305) VENT WITH
1/2 (13)
FOAM
INSULATION
EXHAUST
AIR
12 MIN.
(305)
Above Grade
5-1/2
(140)
GRADE
Side View
8 (203)
Minimum
Inches (mm)
12 (305)
Minimum
ABOVE GRADE
GRADE
9
(229)
EXHAUST
VENT
NOTE- -Enclosed exhaust pipe
is insulated with 1/2” (13mm)
foam insulation. If intake and
exhaust pipes are reversed,
VENT
slit and remove foam insula-
tion and reapply to
vent. Exhaust vent must be
insulated.
12
GRADE
(305)
EXHAUST VENT
8 MIN.
(203)
INTAKE
VENT
GRADE
G21 VENTING IN EXISTING CHIMNEY
8” - - 12”
(203mm - - 305mm)
NOTE- -Do not discharge exhaust gases directly into any chimney or vent
stack. If vertical discharge through an existing unused chimney or stack is re-
quired, insert piping inside chimney until the pipe open end is above top of
chimney and terminate as illustrated. In any exterior portion of chimney, the
exhaust vent must be insulated. An alternate method is to fill the chimney with
vermiculite or equal to take advantage of its acoustic and thermal properties.

GAS PIPING

Gas Supply
The unit is shipped standard for right- -side installation
of gas piping. A piping hole is also fabricated in the left
side for an alternate piping arrangement.
1 - - When connecting the gas supply, factors such as
length of run from the meter, the number of fittings
and furnace rating must be considered to avoid ex-
cessive pressure drop. Table 5 lists recommended
pipe sizes for typical applications.
A drip leg should be installed in the pipe run to the
unit. In some localities, codes may require a man-
other
ual main shut- -off valve and union (furnished by in-
staller) installed external to unit. Union must be of
ground joint type.
A 1/8” (3.2mm) N.P .T. plugged tapping, accessi-
ble for test gauge connection, must be installed
immediately upstream of the gas supply connec-
tion to the furnace.
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2 - - The use of one of the following gas connectors is
recommended:
* ANS Z21.24 Appliance Connectors of Corru-
gated Metal Tubing and Fittings.
* ANS Z21.45 Assembled Flexible Appliance Con-
nectors of Other than All- -Metal Construction.
* For Canadian installations- -All flexible gas con-
nectors must be C.G.A. certified components.
3DJH 
3” - - 8”
(76mm- -
203mm)
3” - - 8”
(76mm- -
203mm)
FIGURE 18
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