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Save These Instructions 3-90-798 Dry Seasoned Wood Only!
Draft is widely misunderstood. It is important that you,
the stove operator, realize that draft is a variable effect,
not a given quantity. Stoves and chimneys do not have
draft, yet draft is the key to your stove’s performance.
Draft is a force, produced by an operating stove and
the chimney to which it is attached. It is created by hot
gases rising up the chimney, creating a pressure differ-
ence between the inside of your home and the outside
air. It continually moves fresh combustion air into the
stove, and hot exhaust gases out of the stove; without
this constant ow, the re will go out.
Other factors, such as barometric pressure, winds,
the airtightness of the home, the total inside chimney
volume, chimney height and the presence of venting
devices such as exhaust fans also play a role in main-
taining an adequate draft. Low barometric pressures,
super insulated homes and exhaust fans can reduce
draft; winds can play havoc with draft; and too large or
too small a chimney volume can cause reduced draft
due to the excessive cooling or not enough room to
vent exhaust gases. Introducing outside air directly to
the stove may help remedy a low draft problem. Some
signs of inadequate draft are smoking, odor, difculty in
maintaining the re, and low heat output. Overdraft can
be caused by a very tall chimney even if it is the recom-
mended size, and can cause overring of your stove.
Signs of an overdraft include rapid fuel consumption, in-
ability to slow the re, and parts of the stove or chimney
connector glowing red. It is important that you follow the
chimney guidelines in this manual, including size, type,
and height to avoid draft problems.
When installed and operated according to this man-
ual, the Oakleaf will produce enough hot gases to keep
the chimney warm so that adequate draft is maintained
throughout the burn cycle.
In general, following these guidelines will ensure
compliance with all national and provincial codes; prior
to beginning your installation, check with your local build-
ing code ofcial to check on additional local regulations
which may inuence the design and placement of your
venting system.
The Harman Oakleaf may be installed with a mini-
mum (.6 mm) 24 gauge chimney connector pipe. The
size of the connector should correspond to the size of
the ue collar opening. Do not use makeshift compro-
mises. No part of the chimney connector may pass
through an attic or roof space, closet or other concealed
space, or through a oor or ceiling. Whenever possible,
avoid passing the connector through a combustible
Depending on your local building codes, and the
pertinent provincial or national codes, there are sev-
eral choices for passing the chimney connector safely
through a wall. Before beginning your installation, con-
tact local ofcials, and also the chimney connector and
chimney manufacturer for specic requirements.
Canada. Three methods are approved by the Cana-
dian Standards Association. The diagram on the next
page shows one method requiring an 18"(450 mm) air
space between the connector and the wall. It allows use
of one or two covers as described in the diagram. The
two other methods are described in detail in the current
issue of CAN/CSA B365, the national standard.
United States In the U.S., the national code is NFPA
211. While many localities adopt this standard, be sure
to check with local authorities before beginning your
installation.
The NFPA (National Fire Protection Agency) permits
four methods for passing through a combustible wall. A
commonly used method to pass through a wall directly
to a masonry chimney is to clear a minimum 12"(300
mm) around the entire chimney connector, and ll it
with brick masonry which is at least 3.5"(90 mm) thick.
A reclay liner, minimum 3/8" (9 mm) wall thickness
must run through the brick wall to the chimney liner (but
not beyond the inner surface of the liner). It must be
cemented in place with refractory cement. This method
is illustrated on the next page. For details on the other
three options, refer to the most recent edition of the
NFPA 211 code.
wall; if you must, use an approved wall pass-through,
described later in this section.
Assemble the connector beginning at the ue collar,
with the crimped ends pointing towards the stove (to
keep debris or residue inside the system). Each joint,
including the one to the stove’s ue collar and the one
to the chimney itself should be secured with at least
three sheet metal screws. Screws may be a maximum
of 3 inches apart. A 1-1/4" (30 mm) overlap is required
at each joint, including the ue collar attachment. No
more than two 90 degree elbows should be used, and
the total length of connector should not exceed 10 feet
(3 m). All horizontal runs of connector must have a
minimum upward slope of 1/4"(6 mm) per foot (20 mm
per meter).
The chimney connector diameter should correspond
to the size of the ue collar opening. Do not use make-
shift compromises. No part of the chimney connector
may pass through an attic or roof cemented in place
with refractory cement.