Page 9
Front Flue / Masonry Chimney
Rear Flue / Masonry Chimney
Liner
Barometric
Draft
Control*
(in either
location)
Clean Out
Liner
Masonry
Chimney
Figure 10
*Barometric draft control may be installed in either vertical or
horizontal section of flue pipe no less than 12” and no more than
18” from furnace flue outlet.
Barometric Draft
Control*
(in either location)
Clean Out
Masonry
Chimney
9 - The vent pipe should slope upward toward the chim
ney on horizontal run at least 1/4 inch (6 mm) to the
foot (0.3 m) and should be supported by something
other than the furnace, such as isolation hangers. See
figure 10.
10 - Extend the vent pipe into the chimney so that it is flush
with the inside of the chimney liner. Seal the joint be
tween the pipe and the liner.
11 - The furnace shall be connected to either a factory-built
chimney or vent which complies with a recognized
standard, or to a masonry or concrete chimney which
has been lined with a material acceptable to the au
thority having jurisdiction.
12 - When two or more appliances vent into a common
vent, the area of the common vent should not be less
than the area of the largest vent or vent connection
plus 50% of the area of the additional vent or vent con
nection. Chimney must be able to sufficiently vent all
appliances operating at the same time.
Front Flue / Factory-Built Chimney
Rear Flue / Factory-Built Chimney
Figure 11
Condensate
Drain
Factory-
Built
Chimney
Barometric Draft
Control*
(in either location)
Barometric Draft
Control*
(in either location)
Factory-
Built
Chimney
Condensate
Drain
*Barometric draft control may be installed in either vertical or
horizontal section of flue pipe no less than 12” and no more than
18” from furnace flue outlet.
13 - The vent pipe shall not be connected to a chimney
vent serving a solid fuel appliance or any mechanical
draft system.
14 - All unused chimney openings should be closed.
15 - All vent pipe run through unconditioned areas or out
side shall be constructed of factory built chimney sec
tions. See figure 11.
16 - Where condensation of vent gas is apparent, the vent
should be repaired or replaced. Accumulation of con
densation in the vent is unacceptable.
17 - Vent connectors serving this appliance shall not be
connected into any portion of mechanical draft sys
tems operating under positive pressure.
18 - Keep the area around the vent terminal free of snow,
ice and debris.