Installation Guide

507332-01 Page 13 of 35Issue 1723
DO NOT insulate the space between the liner and the
chimney wall with puffed mica or any other loose granular
insulating material.
Figure 16. Common Venting Using Metal-Lined
Masonry Chimney
NOTE 1: Refer to the provided venting tables for installations.
Refer to the capacity requirements shown in the provided
venting tables.
A fan assisted furnace may be commonly vented into an
existing lined masonry chimney if the following conditions
are met:
• The chimney is currently serving at least one drafthood
equipped appliance.
• The vent connectors and chimney are sized according
to the provided venting tables.
If type B1 double wall vent is used inside a chimney, no
other appliance can be vented into the chimney. The outer
wall of type B1 vent pipe must not be exposed to ue
products. A type B1 vent or masonry chimney liner shall
terminate above the roof surface with a listed cap or a listed
roof assembly according to the terms of their respective
listings and the vent manufacturer’s instructions.
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. The chimney passageway must be
checked periodically to ensure that it is clear and free of
obstructions.
Do not install a manual damper, barometric draft regulator,
or ue restrictor between the furnace and the chimney.
Never connect a Category I appliance to a chimney that is
servicing a solid fuel appliance. If a replace chimney ue
is used to vent this appliance, the replace opening must
be permanently sealed.
A type B or listed chimney lining system that passes through
an unused masonry chimney ue is not considered to be
exposed to the outdoors.
General Venting Requirements
Vent all furnaces according to these instructions:
1. Vent diameter recommendations and maximum
allowable piping runs are found in the provided venting
tables.
2. In no case should the vent or vent connector diameter
be less than the diameter specied in the provided
venting tables.
3. The minimum vent capacity determined by the sizing
tables must be less than the low re input rating and
the maximum vent capacity must be greater than the
high re input rating.
4. Single appliance vents - If the vertical vent or tile
lined chimney has a larger diameter or ow area than
the vent connector, use the vertical vent diameter to
Figure 17. Common Venting Using Tile Lined Interior Masonry Chimney and Combined Vent Connector
NOTE: Refer to
provided venting tables
for installations.
NOTE: The chimney must be properly
sized per provided venting tables or lined
with listed metal lining system.