Page 6
TABLE 6
Equivalent Area of Masonry Chimney Liners
Nominal Liner Size
(inches X inches)
Inside Liner
Dimensions
(inches)
Inside Diameter or
Equivalent Diameter
(inches)
Equivalent Area
(square inches)
4 X 8
2−1/2 X 6−1/2
4
12.2
5
19.6
6
28.3
7
38.3
8 X 8
6−3/4 X 6−3/4
7.4
42.7
8
50.3
8 X12
6−1/2 X 10−1/2
9
63.6
10
78.5
12 X12
9−3/4 X 9−3/4
10.4
83.3
11
95
12 X 16
9−1/2 X 13−1/2
11.8
107.5
12
113
14
153.9
16 X 16
13−1/4 X 13−1/4
14.5
162.9
15
176.7
16 X 20
13 X 17
16.2
206.1
18
254.4
20 X 20
16−1/2 X 16−3/4
18.2
260.2
20
314.1
Inspection of Tile−Lined Masonry Chimney
The chimney must be inspected and found to be in good
condition. Chimney construction must conform with the
National Fuel Gas Code NFPA 54/ANSI Z223.1, Standard
for Chimneys, Fireplaces, Vents and Solid−Fuel−Burning
Appliances ANSI/NFPA 211, and to any applicable state
or local codes.
The following conditions must be confirmed before
continuing with installation of the vent system:
Chimney must be lined with clay tile.
Chimney crown must be in good condition. Missing
mortar or brick must be replaced.
Tile liner and top seal must be in good condition. If
necessary, make repairs.
All debris (mortar, tile, fuel oil residue, etc.) must be
removed from chimney clean out.
Tile liner must be inspected to make sure that tiles
are properly aligned, that all sections are complete
and that there are no gaps. If necessary, make
repairs.
Exterior chimneys must serve at least one other
drafthood−equipped appliance. Verify before
continuing.
Chimney must be properly sized per these
instructions.
Installation
1 − Turn off all gas supply and electrical power to unit.
WARNING
These instructions must be followed exactly. This
kit must be installed by a qualified service techni-
cian. Improper installation may result in personal
injury, loss of life, equipment damage, or damage to
the existing masonry chimney.
2 − A 7/8" diameter hole is required to accommodate
the conduit for the wiring from the blocked vent
switch in the vent adapter to the pressure switch in
the furnace. A template is provided to ensure proper
location of the hole in the unit top cap.
The conduit hole must be positioned carefully to
avoid contact between the blocked vent switch
wiring and the combustion air inducer or hot
surfaces inside the furnace.
