Page 9
CGA-B149.1 and -B149.2 in Canada. The effective area
of the chimney serving a single appliance must be no
less than the effective area of the draft hood outlet. The
chimney must extend vertically at least 5 feet above the
flue collar.
The G20R gas furnace must not be connected to a
chimney servicing a separate appliance designed to
burn solid fuel.
Masonry chimneys serving fireplaces cannot be used
for venting purposes unless the fireplace opening is
permanently sealed. See figure 10.
When inspection reveals that an existing chimney is
not safe for the intended purpose, it shall be rebuilt to
conform to nationally recognized standards, lined or
relined with suitable materials or replaced with a gas
vent or chimney suitable for venting G20R series units.
The chimney passageway must be checked periodicalĆ
ly to ensure that it is clear and free of obstructions.
G20R
FURNACE
PERMANENTLY
SEALED FIREĆ
PLACE OPENING
H
L
VERTICAL VENT
USING LINED
MASONRY CHIMNEY
FIGURE 10
Removal of Unit from Common Venting System
In the event that an existing furnace is removed from a
venting system commonly run with separate gas apĆ
pliances, the venting system is likely to be too large to
properly vent the remaining attached appliances. The
following test should be conducted while each apĆ
pliance in operation and the other appliances not in opĆ
eration remain connected to the common venting sysĆ
tem. If the venting system has been installed
improperly, the system must be corrected as outlined
in the previous section.
1- Seal any unused openings in the common venting
system.
2- Visually inspect the venting system for proper size and
horizontal pitch and determine there is no blockage or
restriction, leakage, corrosion and other deficiencies
which could cause an unsafe condition.
3- Insofar as is practical, close all building doors and
windows and all doors between the space in which
the appliances remaining connected to the common
venting system are located and other spaces of the
building. Turn on clothes dryers and any appliances
not connected to the common venting system. Turn
on any exhaust fans, such as range hoods and bathĆ
room exhausts, so they will operate at maximum
speed. Do not operate a summer exhaust fan. Close
fireplace dampers.
4- Follow the lighting instructions. Place the appliance
being inspected in operation. Adjust thermostat so
appliance will operate continuously.
5- Test for spillage at the draft hood relief opening after 5
minutes of main burner operation. Use the flame of a
match or candle, or smoke from a cigarette, cigar or pipe.
6- After it has been determined that each appliance reĆ
maining connected to the common venting system
properly vents when tested as outlined above, return
doors, windows, exhaust fans, fireplace dampers and
any other gas-burning appliance to their previous
condition of use.
7- If improper venting is observed during any of the above
tests, the common venting system must be corrected.
Horizontal Venting
This furnace is design certified by the American Gas
Association for horizontal venting through an outside
wall only with the use of a Field Controls Company
Model #SWG-5L side wall venting kit available from
Lennox Dealer Service Center. No other Field brand
venting kit or any other manufacturer's venting kit is acĆ
ceptable. Horizontal venting of this furnace without the
use of the above stated kit is prohibited. See figure 11
for field wiring of side wall horizontal venting kit.
When horizontally vented, minimum clearance for terĆ
mination from electric meters, gas meters, regulators
and relief equipment is 4 ft. (1.2m).
At vent termination, care must be taken to maintain proĆ
tective coatings over building materials (prolonged exĆ
posure to exhaust condensate can destroy protective
coatings). It is recommended that the exhaust outlet not
be located within 6 ft. (1.8m) of a condensing unit beĆ
cause the condensate can damage the painted coating.
SIDE WALL VENTING KIT WIRING
C
L1
L2
120VAC
3
1
PPC-5
(OPTIONAL)
M
L1
M
N
T1 T2 T3
W
R
Y
G
W
G
R
Y
24 VAC
THERMOSTAT
THERMOSTAT CONNECTIONS
TERMINAL IN FURNACE
JUNCTION BOX
RELAY
CK-40 CONTROL BOX
PRESSURE
SWITCH
SWG
POWER
VENTER
MOTOR
A
B
7
5
FIGURE 11
T
FIELD INSTALLED WIRING
FACTORY INSTALLED WIRING
NO
