23800-5-0909
Page 10
Wall furnaces shall be installed in a location in which the facilities for ventilation permit satisfactory combustion of gas and proper
venting under normal conditions. In buildings of conventional frame, brick, or stone construction without tight storm windows and
doors, infiltration is normally adequate to provide air for combustion and draft hood dilution.
Where appliances are installed in confined and unconfined spaces within a building, the building being of unusually tight construction,
air for combustion and ventilation must be obtained directly from outdoors or from such spaces that freely communicate with the
outdoors. Under these conditions, the confined and unconfined spaces shall be provided with two permanent openings, one near the
top of the enclosure and one near the bottom; each opening shall have a free area of not less than one square inch (6.45 cm
2
) per 2,000
BTU (.6KW/H) per hour of total input.
VENTILATION AND COMBUSTION AIR
VENT CAP
GAS VENT
OUTLET AIR
INLET AIR
VENTILATION LOUVERS
FOR UNHEATED CRAWL SPACE
VENTILATION LOUVERS
EACH END OF ATTIC
VENT CAP
GAS VENT
OPENING
ALTERNATE
OPENING
VENT CAP
GAS VENT
OPENING
OPENING
VENT CAP
GAS VENT
OUTLET AIR
INLET
GRILLE
INLET AIR DUCT
(ENDS 1 FT. (300MM)
ABOVE FLOOR
VENTILATION LOUVERS
EACH END OF ATTIC
Figure 10
Figure 12
Figure 11
Figure 13