Venting Using a Masonry Chimney
The following additional requirements apply when a lined masonry chimney is used to vent a G24−200 furnace:
Masonry chimneys used to vent Category I central fur- naces must be either
A Category I appliance must never be connected to a chim- ney that is servicing a solid−fuel appliance. If a fireplace chimney flue is used to vent this appliance, the fireplace opening must be permanently sealed.
A fan−assisted furnace may be commonly vented into an existing lined masonry chimney if the following conditions are met:
1 − The chimney is currently serving at least one drafthood equipped appliance.
2 − 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 B149.1 of the Natural Gas and Propane Installation Code in Canada.
IMPORTANT
SINGLE appliance venting of a
A type B1 vent or masonry chimney liner shall terminate above the roof surface with a listed cap or a listed roof assembly ac- cording to the terms of their respective listings and the vent manufacturer’s instructions.
Do not install a manual damper, barometric draft regula- tor, or flue restrictor between the furnace and the chimney.
If type B1
Insulation for the flexible vent pipe must be an encapsu- lated fiberglass sleeve recommended by the flexible vent pipe manufacturer. See figure 9.
The space between the liner and the chimney wall should NOT be insulated with puffed mica or any other loose granular insulating material.
If B1 vent or an insulated flexible vent pipe cannot be used as liners, the chimney must be rebuilt to accommodate one of these methods or some alternate approved method must be found to vent the appliance.
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 G24−200 units. The chimney passage- way must be checked periodically to ensure that it is clear and free of obstructions.
COMMON VENTING USING METAL−LINED MASONRY CHIMNEY
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| MAX. LENGTH − SEE |
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| NOTE 1 BELOW. |
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NOTE 1 − Refer to the provided venting tables |
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| MIN. LENGTH − AS SHORT |
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5 FT. |
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for installations in the USA and the venting |
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tables in CSA−B149.1 for installations Canada. | (1.5m) |
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SEALED
EXTERIOR CHIMNEY WITH TED
FLEXIBLE VENT PIPE
NOTE 2 − Either
VENT |
CONNECTOR |
SEE NOTE 2 |
G24−200 |
PERMANENTLY 
SEALED FIRE- PLACE OPENING
JOIN HEAT
SECTIONS
WITH A ’TEE−Y’
FIGURE 9
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