Kenmore 153.332319, 153.332419, 153.332463, 153.332363 ALL AIR from Inside Buildings, All Air

Installation Instructions (cont'd)

Combustion Air and Ventilation for Appliances Located in

Unconfined Spaces

Unconfined Space is a space whose volume is not less than 50 cubic feet per 1,000 Btu per hour of the aggregate input rating of all appliances installed in that space. Rooms communicating directly with the space in which the appliances are installed, through openings not furnished with doors, are considered a part of the unconfined space

In unconfined spaces in buildings, infiltration may be adequate

to provide air for combustion, ventilation and dilution of flue

gases. However, in buildings of tight construction (for example, weather stripping, heavily insulated, caulked, vapor barrier, etc.),

additional air may need to be provided using the methods

described in Combustion Air and Ventilation for Appliances Located in Confined Spaces, b.

I. When directly communicating with the outdoors, each open- ing shall have a minimum free area of 1 square inch per 4,000

BTU per hour of total input rating of all equipment in the enclosure. (See Figure 3.)

2. When communicating with the outdoors through vertical

ducts, each opening shall have a minimum free area of 1

square inch per 4,000 BTU per hour of total input rating of all equipment in the enclosure. (See Figure 4.)

Combustion Air and Ventilation for Appliances Located in Confined Spaces

Confined Space is a space whose volume is less than 50 cubic feet per 1,000 Btu per hour of the aggregate input rating of all appliances installed in that space.

a. ALL AIR FROM INSIDE BUILDINGS:

(See Page 9 Figure 1, and Figure 2 below)

The confined space shall be provided with two permanent

openi_ngs communicating directly with an additional room(s)

of sufficient volume so that the combined volume of all

spaces meets the criteria for an unconfined space. The total

input of all _as utilization equipment installed in the com- bined space shall be considered in making this determination. Each opening shall have a minimum free area of one square inch per 1,000 BTU per hour of the total input rating of all

gas utilization equipment in the confined space, but not less than 100 square inches. One opening shall commence within

12 inches of the top and one commencing within 12 inches of the bottom of the enclosure.

b. ALL AIR	FROM		OUTDOORS:		(see Figures 3-5)
The confined		space shall be provided with two permanent
openings, one		commencing		within 12 inches of the top and
one commencing			within	12 inches	from the	bottom	of	the
enclosure.	The	openings		shall communicate		directly,	or	by
ducts, with the outdoors or spaces (crawl or attic) that freely
communicate	with		the outdoors.

I Figure 3 ]

Figure 4 ]

3.When communicating with the outdoors through horizontal

ducts, each opening shall have a minimum free area of 1 sguare inch per 2,000 BTU per hour of total input rating of all equipment in the enclosure. (See Figure 5.)

	___UrLEr CHbM_EY O_ GA_ VEN_ _	A_n OUCh.
[ Figure	5 ]

4, When ducts are used, they shall be of the same cross-sectional area as the free area of the openings to which they connect. The minimum short side dimension of rectangular air ducts shall not be less than 3 inches. (See Figure 5.)

5.Louvers and Grilles: In calculating free area, consideration shall be given to the blocking effect of louvers, grilles or

screens protectin_ openings. Screens used shall not be smaller than ¼ inch mesh. If the free area through a design of louver

or grille is known, it should be used in calculating the size opening required to provide the free area specified. If the design and free area is not known, it may be assumed that wood louvers will be 20-25 percent free area and metal louvers and grilles will have 60-75 percent free area. Louvers and grilles shall be fixed in the open position or interlocked with the equipment so that they are opened automatically during equipment operation.

6.Special Conditions Created by Mechanical Exhausting or

Fireplaces: Operation of exhaust fans, ventilation systems, clothes dryers or fireplaces may create conditions requiring special attention to avoid unsatisfactory operation of installed gas utilization equipment.

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