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114668-01G
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The National Fuel Gas Code, ANSI Z223.1/
NFPA 54
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input rating of all appliances installed in that
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gregate input rating of all appliances installed
in that space. Rooms communicating directly
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* Adjoining rooms are communicating only if
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1. Determine the volume of the space (length
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Length x Width x Height =__________cu. ft.
(volume of space)
Example:
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(volume of space)
If additional ventilation to adjoining room
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volume of these rooms to the total volume
of the space.
2. Multiply the space volume by 20 to determine
the maximum Btu/Hr the space can sup-
port.
________ (volume of space) x 20 = (Maxi-
mum Btu/Hr the space can support)
Example:
2560 cu. ft. (volume of space) x 20
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support)
3. Add the Btu/Hr of all fuel burning appliances
in the space.
AIR FOR COMBUSTION AND VENTILATION
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___________ Btu/Hr
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___________ Btu/Hr
Gas furnace
___________ Btu/Hr
Vented gas heater
___________ Btu/Hr
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___________ Btu/Hr
Other gas appl __________ Btu/Hr
Total
= __________ Btu/Hr
* Do not include direct-vent gas appliances.
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outdoors and vents to the outdoors.
Example:
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___________ Btu/Hr
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__________ Btu/Hr
Total
= __________ Btu/Hr
4. Compare the maximum Btu/Hr the space
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Hr used.
_______ Btu/Hr (maximum the space can
support)
_______ Btu/Hr (actual amount of Btu/Hr
used)
Example:
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space can support)
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Btu/Hr used)
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space because the actual Btu/Hr used is more
than the maximum Btu/Hr the space can sup-
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adjoining room. If the extra space provides
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rooms. See
Ventilation Air From Inside
Building
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.
B. Vent room directly to the outdoors. See
Ventilation Air From Outdoors,
page 8.
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If the actual Btu/Hr used is less than the maxi-
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ditional fresh air ventilation.
