Desa 101811-01C.pdf Air For Combustion And Ventilation, Continued, Ventilated Outlet Attic Air

AIR FOR COMBUSTION AND VENTILATION

Continued

8

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. Follow the National Fuel Gas Code NFPA 54/ANSI Z223.1, Section 5.3, Air for Combustion and Ventilation for required size of ventilation grills or ducts.

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.

Ventilated

Outlet Attic

Air

Outlet
Air	To Attic

To

Crawl

Space

Inlet

Air

Inlet Air	Ventilated
	Crawl Space

Figure 3 - Ventilation Air from Outdoors

101811