14
LP- 428 REV. 9.2.14
2. INDOOR COMBUSTION AIR INSTALLATION IN CONFINED OR UNCONFINED SPACE
This appliance requires fresh, uncontaminated air for safe operation and must be installed in a mechanical room where there is
adequate combustion and ventilating air. NOTE: To prevent combustion air contamination, see Table 1.
Combustion air from the indoor space can be used if the space has adequate area or when air is provided through a duct or louver to
supply sufficient combustion air based on the appliance input. Never obstruct the supply of combustion air to the appliance. If the
appliance is installed in areas where indoor air is contaminated (see Table 1) it is imperative that the appliance be installed as direct
vent so that all combustion air is taken directly from the outdoors into the appliance intake connection.
Unconfined space is space with volume greater than 50 cubic feet per 1,000 Btu/hour (4.8 cubic meters per kW) of the total input
rating of all fuel-burning appliances installed in that space. Rooms connected directly to this space, through openings not furnished with
doors, are considered part of the space.
Confined space is space with volume less than 50 cubic feet per 1,000 Btu/hour (4.8 cubic meters per kW) of the total input rating of
all fuel-burning appliances installed in that space. Rooms connected directly to this space, through openings not furnished with doors,
are considered part of the space.
When drawing combustion air from inside a conventionally constructed building to a confined space, such space should be provided
with two permanent openings: one located 6” (15 cm) below the space ceiling, the other 6” (15cm) above the space floor. Each opening
should have a free area of one square inch per 1,000 Btu/hr (22cm
2
/kW) of the total input of all appliances in the space, but not less
than 100 square inches (645cm
2
).
If the confined space is within a building of tight construction, air for combustion must be obtained from the outdoors as outlined in the
Venting Section of this manual.
When drawing combustion air from the outside into the mechanical room, care must be taken to provide adequate freeze protection.
Do not attempt to vent this appliance by any means other than those described in this manual. Doing so will void the warranty, and may
result in severe personal injury or death.
Failure to provide an adequate fresh combustion air can cause poisonous flue gases to enter living space, which could result in severe
personal injury or death. To prevent combustion air contamination, see Table 1.
F. PREVENT COMBUSTION AIR CONTAMINATION
Install intake piping for the boiler as described in the Venting section. Do not terminate exhaust in locations that can allow
contamination of intake air.
You must pipe outside air to the boiler intake. Ensure that the intake air will not contain any of the contaminants below. For example, do
not pipe intake near a swimming pool. Avoid areas subject to exhaust fumes from laundry facilities. These areas always contain
contaminants. Contaminated air will damage the boiler, resulting in possible substantial property damage, severe personal injury, or
death.
AREAS LIKELY TO HAVE CONTAMINANTS
Spray cans containing fluorocarbons
Dry cleaning/laundry areas and establishments
Chlorinated waxes/cleaners
Chlorine-based swimming pool chemicals
Calcium chloride used for thawing
Refrigeration repair shops
Sodium chloride used for water softening
Paint or varnish removers
Plastic manufacturing plants
Hydrochloric or Muriatic acid
Furniture refinishing areas and establishments
New building construction
Antistatic fabric softeners used in clothes dryers
Chlorine-type bleaches, laundry detergents, and cleaning solvents
Adhesives used to fasten building products
Table 1 – Contaminants
To Next Page
Loading...
Need help?
General
