Specifications

6
Problem Description Can Occur when.. Possible Solutions
The chimney is too high. Increasing the height of a
chimney increases the draft.
Draft increases in proportion
with chimney height but only
to a certain point. At some
point, additional height
gives the ue gases more
time to transfer heat to the
ue walls and cool off. This
will cause a reduction in the
available draft.
If a system meets the
recommended minimum
height and draft problems
are experienced, it may or
may not have any effect to
extend the chimney height.
• The chimney is serving
a replace in a multistory
building (apartment
complex)
• A large part of the chimney
is exposed to the outside.
• Reduce the height
• Insulate the chimney
• Install a mechanical
venting system
The chimney is placed out-
side the building envelope
If one or more sides of a
chimney are exposed to the
outside, the chimney can
experience excess cooling,
which will reduce the draft.
The chilling effect can be so
bad that the exhaust gas is
not able to create any draft
at all – at least not during
start-up. The best
location of a chimney is
within the building so only
a very small part of the
chimney is exposed to the
outside.
• The chimney is installed
on an outside wall.
• The chimney is not
insulated
• The chimney is installed in
a location that meets code
but is detrimental to proper
draft.
• Reline the chimney and/or
provide better insulation
• Install a mechanical
venting system
Obstructions or blockages
in the venting system
A chimney can be
obstructed by debris, such
as leaves, mortar left over
during construction, or an
animal or bird building a
nest. Creosote build-up
could also be blocking the
ue or the chimney cap.
Blockages might occur in
deteriorating chimneys if
parts of the interior
collapses.
• The ue liner is
deteriorating.
• Bird nests have been built
outside the heating season.
• Scan the inside of the
chimney in search for
obstructions blockages.
Repair if deteriorations are
found.
• Remove animal’s nests.
• Clean the chimney for
creosote or debris