AIR FOR COMBUSTION AND VENTILATION
WARNING: This heater shall not be installed in a confined space or unusually tight construction unless provisions are provided for adequate combustion and ventila- tion air. Read the following in- structions to insure proper fresh air for this and other
PROVIDING ADEQUATE VENTILATION
The following are excerpts from National Fuel Gas Code, NFPA 54/ ANSZ 223.1.Section 5.3, Air for Combustion and Ventilation.
All spaces in homes fall into one of the three following ventilation classifications:
1.Unusually Tight Construction
2.Unconfined Space
3.Confined Space
The information on pages 5 through 6 will help you classify your space and provide adequate ventilation.
Confined and Unconfined Space
The National Fuel Gas Code, ANS Z223.1 defines a confined space as a space whose volume is less than 50 cubic feet per 1,000 Btu per hour (4.8 m3 per kw) of the aggre- gate input rating of all appliances installed in that space and an unconfining space as a space whose volume is not less than 50 cubic feet per 1,000 Btu per hour (4.8 m3 per kw) of the aggregate input rating of all appliances in- stalled in that space. Rooms com- municating directly with the space in which the appliances are installed*, through openings not furnished with doors, are consid- ered a part of the unconfined space.
This heater shall not be installed in a confined space or unusually tight construction unless provisions are provided for adequate com- bustion and ventilation air.
*Adjoining rooms are communi- cating only if there are doorless passageways or ventilation grills between them.
Unusually Tight Construction
The air that leaks around doors and windows may provide enough fresh air for combustion and ventilation. However, in buildings of unusually tight construction, you must provide additional fresh air.
Unusually tight construction is defined as construction where:
a)walls and ceilings exposed to the outside atmosphere have a continuous water vapor retarder with a rating of one perm (
b)weather stripping has been added on windows that open and doors and
c)caulking or sealants are ap- plied 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.
If your home meets all of the three criteria above, you must pro-
vide additional fresh air. See Venti- lation Air From Outdoors, page 6. If your home does not meet all of the three criteria above, proceed to Determining
AIR FOR COMBUSTION AND VENTILATION
DETERMINING FRESHAIR FLOW FOR HEATER LOCATION
Determining if |
| You Have a Confined or Unconfined Space |
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Use this worksheet to determine if you have a confined or unconfined space. |
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Space: Includes | the room in which you will install | heater plus any | adjoining rooms with doorless | passageways | ||||||||
or ventilation | grills | between | the | rooms. |
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1. Determine | the | volume of | the space (length width |
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Length Width | Height= |
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Example: Space size 20ft. (length) 16ft. ( width) |
| 8ft. (ceiling height)=2560 cu. ft. (volume of space) | ||||||||||
If additional | ventilation to adjoining room is supplied with grills | or openings, add the volume | of these | |||||||||
rooms to | the | total volume of | the space. |
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2.Divide the space volume by 50 cubic feet to determine the maximum Btu/Hr the space can support. (volume of space)÷50 cu. ft.=(Maximum Btu/Hr the space can support)
Example: 2560 cu. ft. (volume of space)÷50 cu.ft.=51.2 or 51,200(maximum Btu/Hr the space can support)
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