V air for combustion and ventilation – Crown Boiler AWI128 User Manual
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4)
The boiler should be located as close to the chimney as possible.
5)
Do not install this boiler over carpeting.
6)
Do not install this boiler directly on a surface that may get wet. Raise the boiler on a pad.
V Air for Combustion and Ventilation
Sufficient fresh air must be supplied for combustion, ventilation and flue gas dilution. Provisions for combustion, ventilation and
flue gas dilution air for gas utilization equipment vented by natural draft must be made in accordance with local building codes or,
in absence of such codes, in accordance with sections 5.3.3 and 5.3.4 (“Air for Combustion and Ventilation”) of the National Fuel
Gas Code, NFPA 54/ANSI Z 223.1.
To ensure an adequate supply of combustion, ventilation and flue gas dilution air supply, start by determining whether the boiler is
to be installed in a building of unusually tight construction. A building of unusually tight construction is defined by the National
Fuel Gas Code as having all of the following features:
•
Walls and ceilings exposed to outside atmosphere have a continuous water vapor retarder with a rating of 1 perm or
less with openings gasketed and sealed
•
Weather stripping has been added on openable windows and doors
•
Caulking and sealants are applied to areas such as joints around window and door frames, between sole plates and
floors, between wall-ceiling joints, between wall panels, at penetrations for plumbing, electrical, and gas lines, and at
other openings.
For Buildings of Other than Unusually Tight Construction
1)
Determine whether the boiler is to be installed in a confined space - A confined space is defined by the National Fuel Gas
Code as having a volume less than 50 cubic feet per 1000 BTU/hr input of all appliances installed in that space. To determine
whether the boiler room is a confined space:
a.
Total the input of all appliances in the boiler room in thousands of BTU/hr. Round the result to the next highest
1000 BTU/hr.
FIGURE 2: CLEARANCE FROM BOILER TO ALL TYPES OF COMBUSTIBLE CONSTRUCTION AND
NONCOMBUSTIBLE CEILINGS, WALLS AND DOORS
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