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AIR FOR COMBUSTION AND VENTILATION Cont.
Ventilation Air From Outdoors
Provide extra fresh air by using ventilation grills or ducts. You must provide two permanent openings: one within 12” of the
ceiling and one within 12” of the floor. Connect these items directly to the outdoors or spaces open to the outdoors. These
spaces include attics and crawl spaces.
IMPORTANT:
Do not provide openings for inlet or outlet air into attic if attic has a thermostat-controlled power vent.
Heated air entering the attic will activate the power vent.
FIGURE 6 - Ventilation Air from Outdoors