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8390-975
Vermont Castings • Defiant® Model 1975-CAT-C Installation Manual_R8 • 02/21
2' Min.
2' Min.
3'
Min.
0 To 10'
3'
Min.
0 To 10'
AC617
RLTSKC8
2/11/98
Reference
Point
Figure 2.2
- The 2’-3’10’ Chimney Rule.
Masonry Chimneys
An inspection of the chimney must confirm that it has a lining.
Do not use an unlined chimney. The chimney should have
no cracks, loose mortar, other signs of deterioration, and
blockage. Repair any defects before the chimney is used
with your stove.
Unused openings in an existing masonry chimney must be
sealed with masonry to the thickness of the chimney wall,
and the chimney liner should be repaired. Openings sealed
with pie plates or wallpaper are a hazard and should be
sealed with mortar or refractory cement. In the event of a
chimney fire, flames and smoke may be forced out of these
unused thimbles.
The chimney should be thoroughly cleaned before use.
A newly-built masonry chimney must conform to the
standards of your local building code or, in the absence of a
local code, to a recognized national code. Masonry chimneys
must be lined, either with code-approved masonry or pre-cast
refractory tiles, stainless steel pipe, or a code-approved,
“poured-in-place” liner. The chimney’s clean-out door must
seal tightly. A loose or leaky clean-out door can weaken
chimney draft, causing performance problems.
Prefabricated Chimneys
A prefabricated metal chimney must be one tested and
listed for use with solid-fuel burning appliances to the High-
Temperature (H.T.) Chimney Standard UL-103-1985 (2100°F)
for the United States, and High Temperature (650°C) Standard
ULC S-629 for Canada.
DO NOT CONNECT THIS UNIT TO A CHIMNEY FLUE
SERVING ANOTHER APPLIANCE.
C. Chimney Size
This appliance with an 8" (203 mm) flue collar is approved
for venting into a masonry chimney with a nominal flue size
of 8" x 8" (203 x 203 mm) or 8" x 12" (203 x 305 mm), and
into a round flue with nominal flue size of 8" (203 mm). This
appliance with a 6" (152 mm) flue connector is approved for
venting into a masonry chimney with a nominal flue size of
8" x 8" (203 x 203 mm), and into a round flue with nominal
flue of 6" (152 mm).
Whatever the flue collar size, this appliance may be vented
into larger chimneys as well. However, chimneys with
liners larger than 8" x 12" (203 x 305 mm) may experience
rapid cooling of smoke and reduction in draft, especially if
the chimneys are located outside the home. These large
chimneys may need to be insulated or have their flues relined
for proper stove performance.
Accessories to help make the connection between stainless
steel chimney liners and your appliance are available through
your local dealer.
D. Chimney Connector Guidelines
A chimney connector is the single-wall pipe that connects
the stove to the chimney. The chimney itself is the masonry
or prefabricated structure that encloses the flue. Chimney
connectors are used only to connect the stove to the chimney.
Single-wall connectors should be made of 24 gauge or
heavier steel. Do not use galvanized connector; it cannot
withstand the high temperatures that can be reached by
smoke and exhaust gases, and may release toxic fumes
under high heat. The connector may be 6" (152 mm) or 8"
(203 mm) in diameter.
If possible, do not pass the chimney connector through a
combustible wall or ceiling. If passage through a combustible
wall is unavoidable, refer to the section on Wall Pass-
Throughs. Do not pass the connector through an attic, a closet
or similar concealed space. The whole connector should be
exposed and accessible for inspection and cleaning.
ST241
chimney types
12/13/99 djt
A prefabricated double-wall
insulated chimney
A tile-lined
masonry chimney
Figure 2.1
- Approved chimney types.
If you use an existing masonry chimney, it must be inspected
to ensure it is in a safe condition before the stove is installed.
Your local professional chimney sweep, building inspector,
or fire department official will be able to inspect the chimney
or provide a referral to someone who can.
The chimney must extend at least 3’ (914 mm) above the
highest point where it passes through or near a roof, and at
least 2’ (610 mm) higher than any part of a building within
10’ (3 m) horizontally. (Figure 2.2)
For proper draft and good performance, any chimney used
should extend at least 16’ (5 m) above the flue collar of the
stove.
