A.O. Smith ATX-199 Instruction Manual page 20

2 2
2
2 2
(100 in ).
•
•
•
2 ).
•
area of the opening.
•
•
•
•
Check that Air Source is Clean and Free of Chemicals
Table 6
Table 6. Minimum Free Area by Ventilation Type
Opening Source
2 (865
openings
2
Z223.1/NFPA 54
Combustion Air Supply Options
Figure 8 through Figure 12
Alternate
Air Inlet
2
per 4,000 btu/h
Figure 8. Air from Outdoors Openings
Two permanent
Openings
2 2
1 in (6.5 cm )
per 4,000 btu/h
Figure 9. Outdoor Air Through Two Openings
20
Minimum Free Area
2 2
1 in
Figure 8 Figure 9.)
2 2
1 in
Figure 13.)
2 2
1 in
Figure 10.)
2 2
1 in
Figure 11.)
2 2
1 in
Figure 12.)
2
(645
National Fuel Gas Code ANSI
Gable vent
to outdoors
Install above
Outlet air to
2
per 4,000 btu/h
2 )
12" (305 mm)
maximum
Space
12" (305 mm)
maximum
(See
2
) MIn
2 )