Openings For Combustion Air Supply And Venting - Buderus LOGANO PLUS GB312 Installation Instructions Manual

5

Openings for combustion air supply and venting

5 Openings for combustion air supply and
venting
To ensure an adequate combustion air supply and venting of the heating
system, suitable measures must be taken in accordance with the
National Fuel Gas Code, NFPA 54 (ANSI Z 223.1), Section 5.3, Air for
Combustion and Ventilation, or the local building code. In Canada the
regulations in accordance with CAN/CSA B149.1 and 2 Installation
Codes apply.
CAUTION: Risk of boiler damage and malfunctions due
to missing or inadequate openings for combustion air
and venting of the boiler room.
The openings for combustion air supply and venting are
always required regardless of whether the combustion
air is supplied from the room (operation from room air)
or directly to the boiler through ducts (operation
independent of room air). Inadequate venting of the
boiler room may result in excessive ambient
temperatures. This can damage the boiler.
Inadequate combustion air supply may cause
malfunctions in operation.
▶ Make sure that air inlet or outlet vents are not closed
off or their size reduced and that they are adequately
dimensioned.
▶ The boiler must not be operated until the obstruction
has been removed.
▶ Draw the operator's attention to any deficiencies and
the potential dangers.
CAUTION: Risk of boiler damage from contaminated
combustion air!
▶ Never use cleaning agents that contain chlorine or
halogenated hydrocarbons (e.g. in spray cans,
solvents and cleaning agents, paints, glues).
▶ Do not store or use such substances in the boiler
room.
▶ Avoid excessive dust accumulation.
If impurities in the combustion air are possible (e.g.
installation near swimming pools, dry cleaners or
hairdressing salons), sealed combustion operation is
recommended.
CAUTION: Dangers posed by explosive and easily
combustible materials.
▶ Do not use or store easily-combustible materials
(paper, lace curtains, clothing, thinners, paints, etc.)
near the boiler.
▶ Maintain a clearance of 16 inches from the boiler.
16
Overall air supply within the building
Make sure that the boiler room has two permanent air vents that are
connected to one or more other rooms. When calculating the cross-
sectional areas of the vent apertures, the total burner output of all gas-
fired appliances in the connected rooms must be taken into account.
Each vent must have a minimum cross-section of one square inch per
1000 Btu/h of the total burner output of all gas-fired appliances inside
the connected rooms. Make sure that the cross-sectional area of each
vent is at least 100 square inches. One of the vents must be no more
than 12" from the ceiling and the other no more than 12" from the floor
of the boiler room, measured from the outer edge of the vent aperture.
The smallest dimension of all inlet and outlet vents must be not less
than 3".
Total air supply from outside the building
Make sure that the boiler room has two permanent air vents, one of
which must not be more than 12" from the ceiling and the other not more
than 12" from the floor of the boiler room, measured from the outer edge
of the vent aperture. The vents must be connected either directly or via
air ducts to the outside or to rooms that have an unobstructed
connection to the open air (crawl passage or roof space). The smallest
dimension of all inlet and outlet vents must be not less than 3".
• If there is a direct connection to the outside, each opening must have
a minimum cross-section of one square inch per 4000 Btu/h of the
total combustion output of all gas-fired appliances inside the closed
room.
• If there is a connection to the outside through a ventilated attic with
vertical ventilation ducts, each vent aperture must have a minimum
cross-section of one square inch per 4000 Btu/h of the total burner
output of all gas-fired appliances inside the closed room. The attic
must be ventilated at both ends of the house.
• If there is a connection to the outside through horizontal ventilation
ducts, each vent aperture must have a minimum cross-section of one
square inch per 2000 Btu/h of the total burner output of all gas-fired
appliances inside the closed room.
The duct cross sectional area must not be smaller than the free area of
the inlet.
• If there is a connection to the outside through a ventilated attic and
ventilated crawl space, each opening must have a minimum cross-
section of one square inch per 4000 Btu/h of the total burner output
of all gas-fired appliances inside the closed room. The attic must be
ventilated at both ends of the house.
Logano plus GB312 – 6 720 647 367 (2012/11)