Dunkirk XEB-2 Installation Instructions Manual page 6

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One permanent opening commencing with 12
inches of the top of the enclosure, shall be
permitted where the equipment has clearance
of at least 1 inch from the sides and back and
6 inches form the front of the appliance. The
opening shell directly communicate with the
outdoors or shall communicate through a vertical
or horizontal duct to the outdoors or spaces
(crawl or attic) that freely communicate with
the out doors, and shall have a minimum free
area of:
a) 1 sq. inch per 3000 Btu per hour of the total
input of all equipment located in the enclosure
(See Fig. 4), and the front of the appliance
b) Not less than the sum of the areas of all
vent connectors in the confined space.
1 Square Inch )er 4,000 Btuh
100% Free 75% Free 25% Free
Area Area Area
Fresh Air 1/4" Wire Metal Wood
Duct Size Mesh Louvers Louvers
3" x 12" 144,000 108,000 36,000
8" x 8" 256,000 192,000 64,000
8" x 12" 384,000 288,000 96,000
81/2" x 16" 512,000 384,000 128,000
1 Square Inch )er 2,000 Btuh
100% Free 75% Free 25% Free
Area Area Area
Fresh Air 1/4" Wire Metal Wood
Duct Size Mesh Louvers Louvers
3" x 12" 72,000 54,000 18,000
8" x 8" 128,000 96,000 32,000
8" x 12" 192,000 144,000 48,000
81/2" x 16" 256,000 192,000 64,000
1 Square Inch )er 3,000 Btuh
100% Free 75% Free 25% Free
Area Area Area
Fresh Air 1/4" Wire Metal Wood
Duct Size Mesh Louvers Louvers
3" x 12" 108,000 81,000 27,000
8" x 8" 192,000 144,000 48,000
8" x 12" 288,000 216,000 72,000
81/2" x 16" 384,000 288,000 96,000
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