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111826-02C
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6
AIR FOR COMBUSTION AND
VENTILATION
Continued
Figure 3 - Ventilation Air from Outdoors
Figure 2 - Ventilation Air from Inside Building
Outlet
Air
Ventilated
Attic
Outlet
Air
Inlet
Air
Inlet Air
Ventilated
Crawl Space
To
Crawl
Space
To Attic
Or
Remove
Door into
Adjoining
Room,
Option
3
Ventilation Grills
Into Adjoining Room,
Option 2
Ventilation
Grills
Into Adjoining
Room,
Option 1
12"
12"
AIR FOR COMBUSTION AND VENTILATION
Ventilation Air (Cont.)
the outdoors or spaces open to the outdoors. These spaces include
attics and crawl spaces. Follow the National Fuel Gas Code, ANSI
Z223.1/NFPA 54, Section 5.3, Air for Combustion and Ventilation
for required size of ven ti la tion grills or ducts.
IMPORTANT:
Do not provide openings for inlet or outlet air into
attic if attic has a ther mo stat-controlled power vent. Heated air
entering the attic will activate the power vent.