(b) All Air From Outdoors:
The confined space shall be provided with two permanent openings,
one within 12 inches of the top and another within 12 inches of the
bottom of the enclosure. The openings shall communicate directly, or
by ducts, with the outdoors or crawl or attic spaces which
communicate freely with the outdoors.
Direct To Outdoors, See Figure 8.
Chimney
Ventallation Louvers
(each end of attic)
Outlet Air
Note: The inlet
and outlet air
openings shall
each have a
free area of
not less than
one square
inch per 4,000
Btu per hour of
total input
rating of all
equipment in
the enclosure.
Alternative
Air Inlet
Inlet Air
Ventallation Louvers for Unheated Crawl Space
Figure 8.
With Vertical Ducts See Figure 9.
Chimney
Ventallation Louvers
(each end of attic)
Note: The inlet
and outlet shall
each have a free
area of not less
than one square
inch per 4,000
Btu per hour of
the total input
rating of all
equipment in the
enclosure.
Outlet Air
Inlet Air Duct
(ends 1 ft. above floor)
Figure 9.
Installation, Operation, And Service Instructions
15
