Fresh Air
11
Combustion Air Supply
Codes
Provisions for combustion and
ventilation air must be made in
accordance with applicable local codes.
In the absence of local codes, use:
H
CSA B-139 for oil installations in
Canada, or
H
NFPA 31, Standard for the Installation
of Oil Burning Equipment in the U.S.
Always use latest editions of codes.
General
This equipment requires fresh air for
safe operation and must be installed
ensuring provisions for adequate
combustion and ventilation air exist.
Whenever possible, install boiler near an
outside wall so that it is easy to duct
fresh air directly to the boiler area.
The boiler location must never be under
negative pressure. Exhaust fans, attic
fans, or dryer fans may cause air to be
exhausted at a rate higher than air can
enter the structure for safe combustion.
The heating contractor shall ensure all
of the following requirements are met:
H
An adequate supply of combustion air
must be available to ensure proper
combustion.
H
Ambient air temperatures must be
maintained within safe operating
limits.
H
When a damper is provided in any
opening intended to admit combustion
air into the room within which the
appliance is installed, the damper shall
be interlocked to prevent any burner
from starting before the damper is
fully open.
H
Each duct used to convey air from the
outdoors shall have:
1.
A cross-sectional area throughout
its length at least equal to the free
area of the inlet and outlet
openings which it connects,
2.
A minimum dimension of
3” / 76 mm at any cross-section,
3.
When making provision for outside
combustion air, the intake shall not
be less than 1 ft / 0.3 m above the
anticipated snow level for the
location.
H
The heating contractor must check
with local authorities (municipal
building department, gas utility) for
combustion air requirements particular
to the area.
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7
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Failure to provide an adequate supply
of fresh combustion air can cause
poisonous flue gases to enter living
space. Flue gases entering living
space can cause carbon monoxide
poisoning which can result in severe
personal injury or loss of life.
WARNING
Never cover the boiler or store debris
or other materials near the boiler, or
in any way block the flow of
adequate fresh air to the boiler. Never
cover the combustion air opening.
Advise system operator/ultimate
owner accordingly.
WARNING
The boiler must not be located in
areas or rooms where chemicals are
stored, or aggressive vapors (i.e.
bleach, hair spray, methyl chloride,
carbon tetrachloride or
perchloroethylene) or high dust levels
or humidity levels are present. Heat
exchanger corrosion might occur and
reduce the lifetime of the boiler
significantly. If above criteria are not
properly observed and boiler damage
results, any warranty on the complete
boiler and related components will be
null and void.
WARNING