Harman Stove Company 1-90-79700 Chimneys and Venting, Draft, Wall Pass-thrus, Chimney Connectors

Oakleaf Woodburning Stove

5			The Chimney Connector Shall Not Pass Through an
	Chimneys and Venting		Attic or Roof Space, Closet or Similar Concealed Space,
			a Floor or Ceiling.
A. Draft			Assemble the connector beginning at the flue collar,
Draft is widely misunderstood. It is important that			with the crimped ends pointing towards the stove (to
you, the stove operator, realize that draft is a variable			keep debris or residue inside the system). Each joint,
effect, not a given quantity. Stoves and chimneys			including the one to the stove’s flue collar and the one
			to the chimney itself should be secured with at least
do not have draft, yet draft is the key to your stove’s
			three sheet metal screws. Screws may be a maximum
performance.
			of 3 inches apart. A 1-1/4" (30 mm) overlap is required
Draft is a force, produced by an operating stove
			at each joint, including the flue collar attachment. No
and the chimney to which it is attached. It is created by
			more than two 90 degree elbows should be used, and
hot gases rising up the chimney, creating a pressure			the total length of connector should not exceed 10 feet
difference between the inside of your home and the			(3 m). All horizontal runs of connector must have a
outside air. It continually moves fresh combustion air			minimum upward slope of 1/4"(6 mm) per foot (20 mm
into the stove, and hot exhaust gases out of the stove;			per meter).
without this constant flow, the fire will go out.			The chimney connector diameter should correspond
Other factors, such as barometric pressure,			to the size of the flue collar opening. Do not use
winds, the airtightness of the home, the total inside			makeshift compromises. No part of the chimney
			connector may pass through an attic or roof cemented
chimney volume, chimney height and the presence
			in place with refractory cement.
of venting devices such as exhaust fans also play a
			C. Wall Pass-thrus
role in maintaining an adequate draft. Low barometric
pressures, super insulated homes and exhaust fans can			Depending on your local building codes, and the
reduce draft; winds can play havoc with draft; and too			pertinent provincial or national codes, there are several
large or too small a chimney volume can cause reduced			choices for passing the chimney connector safely
draft due to the excessive cooling or not enough room			through a wall. Before beginning your installation,
to vent exhaust gases. Introducing outside air		directly	contact local officials, and also the chimney connector
to the stove may help remedy a low draft problem.			and chimney manufacturer for specific requirements.
Some signs of inadequate draft are smoking, odor,
			Canada. Three methods are approved by the
difficulty in maintaining the fire, and low heat output.
			Canadian Standards Association. The diagram on the
Overdraft can be caused by a very tall chimney even if
			next page shows one method requiring an 18"(450 mm)
it is the recommended size, and can cause overfiring
			air space between the connector and the wall. It allows
of your stove. Signs of an overdraft include rapid fuel
			use of one or two covers as described in the diagram.
consumption, inability to slow the fire, and parts of the
			The two other methods are described in detail in the
stove or chimney connector glowing red. It is important
			current issue of CAN/CSA B365, the national standard.
that you follow the chimney guidelines in this manual,
			United States In the U.S., the national code is NFPA
including size, type, and height to avoid draft problems.
			211. While many localities adopt this standard, be sure
When installed and operated according to this
			to check with local authorities before beginning your
manual, the Oakleaf will produce enough hot gases
to keep the chimney warm so that adequate draft is			installation.
maintained throughout the burn cycle.			The NFPA (National Fire Protection Agency) permits
B. Chimney Connectors			four methods for passing through a combustible wall. A
In general, following these guidelines will ensure			commonly used method to pass through a wall directly
compliance with all national and provincial codes;			to a masonry chimney is to clear a minimum 12"(300
prior to beginning your installation, check with your			mm) around the entire chimney connector, and fill it
local building code official to check on additional			with brick masonry which is at least 3.5"(90 mm) thick.
local regulations which may influence the design and			A fireclay liner, minimum 3/8" (9 mm) wall thickness
placement of your venting system.			must run through the brick wall to the chimney liner (but
The Harman Oakleaf may be installed with a minimum
			not beyond the inner surface of the liner). It must be
(.6 mm) 24 gauge chimney connector pipe. The size of
			cemented in place with refractory cement. This method
the connector should correspond to the size of the flue
collar opening. Do not use makeshift compromises. No			is illustrated on the next page. For details on the other
part of the chimney connector may pass through an			three options, refer to the most recent edition of the
attic or roof space, closet or other concealed space,			NFPA 211 code.
or through a floor or ceiling. Whenever possible, avoid
passing the connector through a combustible wall; if you
must, use an approved wall pass-through, described
later in this section.
Save These Instructions		3-90-798	Dry Seasoned Wood Only!	13