Riello 20165080, Installation, Operation And Service Manual

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38
INSTALLATION
2.12.3 Combustion air from outside the building
Two permanent openings method
If outside combustion air is required, the room shall have two per-
manent louvered openings to the outdoors. Each opening must
have a minimum free area of 1 square inch for each 4.000 Btu/hr of
total input rating of all fuel burning equipment in the space. When
the air is supplied to the room via ducts, two ducts must be used.
Vertical ducts and openings must have a minimum free area of
1 square inch for each 4.000 Btu/hr of the total input rating of all
fuel burning equipment in the space. Horizontal ducts and open-
ings must have a minimum free area of 1 square inch for each
2.000 Btu/hr of the total input rating of all fuel burning equipment
in the space.
One permanent opening method
If outside combustion air is required, the room shall have one
permanent louvered opening to the outdoors. The opening must
communicate directly with the outdoors or through a duct in ei-
ther a vertical or horizontal arrangement. The opening must have
a minimum free area of 1 square inch for each 3.000 Btu/hr of total
input rating of all fuel burning equipment in the space.
The free area of the opening must take into account restrictions
from louvers and screens. The louver manufacturer should be
consulted for the percentage of free area available. When free
area is not known, metal louvers typically have 60-70% of free
area, wooden louvers have between 20-25% of free area. Lou-
vers should be in a fixed position or interlocked with equipment
so that they open automatically during equipment operation. The
combustion air damper opening shall be located as follows: top
louver shall begin within 12” of the ceiling and the bottom louver
within 12” of the floor as prescribed in NFPA 54.
Direct intake method
If outside combustion air is required, air may be drawn from the
outdoors via a duct connected directly to the burner intake. The
duct shall be constructed of galvanized steel or a material having
equivalent strength and rigidity. Refer to the burner manufactur-
er's recommendations and installation instructions for additional
guidelines and application requirements.
2.12.4 Combustion air from an adjacent room
Where combustion air is to be used from within the building, air
must be provided into the equipment room through two perma-
nent openings into the interior building. Each opening must have
a minimum free area of 1 square inch for each 1.000 Btu/hr of the
total input rating of all fuel burning equipment in the space. The
louvers shall be located as follows: top louver shall start within
12” of the ceiling and the bottom louver within 12” of the floor as
prescribed in NFPA 54.
2.12.5 Condensate removal
The exhaust vent pipe must be pitched at least 1/4“ per foot of
length back to the boiler. This will allow condensate to drain back
to the unit to be disposed. Low spots in the venting where con-
densate may collect should be avoided. A plastic hose or PVC drain
pipe may be used to discharge condensate to the neutralization
system. Care should be taken to avoid kinks and from raising the
drain line above the trap assembly.