To avoid a blocked vent condition, keep the vent cap
clear of snow, ice, leaves, debris, etc.
Flue gases will form a white plume in winter. Plume
could obstruct window view.
Flue gas condensate can freeze on exterior sur fac es or
on the vent cap. Frozen condensate on the vent cap can
result in a blocked vent condition. Flue gas condensate
can cause discoloration of exterior build ing surfaces.
Adjacent brick or masonry sur fac es should be protected
with a rust resistant sheet metal plate.
A masonry chimney must be properly sized for the
installation of a gas fired appliance. Venting of an
appliance into a cold or oversized masonry chimney can
result in op er a tion al and safety problems. Exterior
masonry chim neys, with one or more sides exposed to
cold out door tem per a tures, are more likely to have
venting problems. The temperature of the flue gases
from an appliance may not be able to suf fi cient ly heat
the ma son ry structure of the chim ney to generate proper
draft. This will result in condensing of flue gases,
damage the masonry flue/tile, insufficient draft and
possible spill age of flue gases into an occupied living
space. Care ful ly in spect all chimney systems before
installation. If there is any doubt about the sizing or
condition of a masonry chimney, it must be relined with
a prop er ly sized and approved chimney liner system.
Inspection of a Masonry Chimney
A masonry chimney must be carefully inspected to
determine its suitability for the venting of flue gas es. A
clay tile lined chimney must be structurally sound,
straight and free of misaligned tile, gaps between
liner sections, missing sections of liner or any signs
of con den sate drainage at the breaching or clean
out. If there is any doubt about the condition of a
masonry chimney, it must be relined. An unlined
masonry chimney must not be used to vent flue
gases from this appliance. An unlined chimney must be
relined with an approved chimney liner system when a
new appliance is be ing attached to it. Metallic liner
systems (Type “B” double wall or flexible or rigid
metallic liners) are recommended. Consult with local
code officials to determine code requirements or the
advisability of using or relining a masonry chimney.
FIG. 14 Sidewall Venting with an Induced Draft Fan
This appliance is NOT approved for sidewall venting
with the negative draft venting system as shipped from
the factory. An induced draft fan MUST be used if the
installation requires that the flue gases be vented out a
sidewall. A properly sized and in stalled induced draft
fan may also be used to vent the flue gases ver ti cal ly if
required by jobsite re stric tions. The induced draft fan
must be listed by a nationally recognized test agency, be
properly sized and installed per the rec om men da tions of
the in duced draft fan manufacturer and meet local code
requirements. Use care to ensure that the me chan i cal -
ly supplied draft does not exceed the range of a
negative 0.02 to 0.05 inches water column to ensure
proper operation. If draft exceeds the spec i fied range,
the fan must be adjusted or the installation of a baro -
met ric damper in the flue may be required to prop er ly
control draft. An induced draft fan MUST be
interlocked into the appliance’s control circuit to start
when the appliance calls for heat. The in duced draft fan
MUST also be equipped with a prov ing switch,
properly interlocked into the ap pli ance’s con trol circuit
to prove fan operation before the main burn ers are
allowed to fire. A vertical or sidewall vent termination
for an induced draft fan MUST be in stalled per the
recommendations of the fan manufacturer and provide
proper clearances from any combustion or ventilation
openings, win dows, doors or other open ings into the
building. All induced draft fan in stal la tions must
comply with local code requirements.
10
SIDEWALL VENTING
Examine the venting system at least once a year.
Check all joints and vent pipe con nec tions for
tightness. Also check for corrosion or
de te ri o ra tion. Immediately correct any problems
ob served in the venting system.
IMPORTANT
MASONRY CHIMNEY
INSTALLATION
