Page 12
506178−01 05/2009
Venting Using a Masonry Chimney
The following additional requirements apply when a lined
masonry chimney is used to vent this furnace.
Masonry chimneys used to vent Category I central fur-
naces must be either tile-lined or lined with a listed metal
lining system or dedicated gas vent. Unlined masonry
chimneys are prohibited. See figures 11 and 12 for com-
mon venting.
A chimney with one or more sides exposed to the outside of
the structure is considered to be an exterior chimney.
An exterior masonry chimney that is not tile−lined must be
lined with B1 vent or a listed insulated flexible metal vent.
An exterior tile−lined chimney that is sealed and capped
may be lined with a listed uninsulated flexible metal vent.
If the existing chimney will not accommodate a listed metal
liner, either the chimney must be rebuilt to accommodate
one of these liners or an alternate approved venting meth-
od must be found.
Insulation for the flexible vent pipe must be an encapsu-
lated fiberglass sleeve recommended by the flexible vent
pipe manufacturer. See figure 11.
IMPORTANT
SINGLE appliance venting of a fan-assisted furnace
into a tile-lined masonry chimney (interior or outside
wall) is PROHIBITED. The chimney must first be lined
with either type B1 vent or an insulated single wall
flexible vent lining system which has been sized ac-
cording to the provided venting tables and the vent
pipe manufacturer’s instructions.
DO NOT insulate the space between the liner and the
chimney wall with puffed mica or any other loose gran-
ular insulating material
A fan−assisted furnace may be commonly vented into an
existing lined masonry chimney if the following conditions
are met:
S
The chimney is currently serving at least one drafthood
equipped appliance
S
The vent connectors and chimney are sized according
to the provided venting tables for the USA, and the ap-
propriate venting tables in the standards of CSA B149
Natural Gas and Propane Installation Codes in Cana-
da.
Common Venting Using Metal−Lined Masonry Chimney
4 in. (102 mm)
minimum
MIN. LENGTH −− AS
SHORT AS PRACTICAL
MAX. LENGTH
−− SEE NOTE 1
BELOW.
SEALED
PERMANENTLY
SEALED FIREPLACE
OPENING
EXTERIOR
CHIMNEY WITH
METAL
LINER
VENT CONNECTOR
SEE NOTE 2
NOTE 1 − Refer to the provided venting tables for installations in the USA
and the venting tables in CSA−B149 for installations Canada.
NOTE 2 − Either single-walled or double-walled vent connector may be
used. Refer to the capacity requirements shown in the provided venting
tables for installations in USA and the venting tables in current CSA−
B149 for installations in Canada.
OTHER
APPLIANCE
FURNACE
FIGURE 11
5 ft. (1.5 m)
minimum
Common Venting Using Tile−Lined Interior Masonry Chimney and Combined Vent Connector
MINIMUM LENGTH = AS SHORT AS PRACTICAL.
FOR MAXIMUM LENGTH SEE NOTE TO LEFT
INTERIOR TILE−LINED
MASONRY CHIMNEY
NOTE − the chimney must be properly
sized per provided venting tables or
lined with listed metal lining system.
PERMANENTLY
SEALED FIREPLACE
OPENING
VENT
CONNECTOR
SEE NOTE 1 BELOW
NOTE − Either single-walled or double-walled vent connector may be used. Refer to the capacity requirements as shown in the pro-
vided venting tables for installations in USA and the venting tables in current CSA−B149 for installations in Canada.
NOTE− Refer to provided venting tables
for installations in the USA and the
venting tables in current CSA−B149 for
installations in Canada.
FURNACE
OTHER
APPLIANCE
FIGURE 12
