Desa CDR3924PT installation manual Ventilation AIR, Ventilation Air From Inside Building

AIR FOR COMBUSTION

AND VENTILATION

Continued

A.	Rework worksheet, adding the space of an adjoin-
	ing room. If the extra space provides an unconfined
	space, remove door to adjoining room or add
	ventilation grills between rooms. See Ventilation
	Air From Inside Building.
B.	Vent room directly to the outdoors. See Ventila-
	tion Air From Outdoors, page 7.

Ventilation
Grills
Into Adjoining	Or
Room,
	Remove
Option 1
	Door into
	Adjoining
	Room,
	Option
	3

12"

Ventilation Grills

Into Adjoining Room,

Option 2

C. Install a lower Btu/Hr heater, if lower Btu/Hr size

makes room unconfined.

If the actual Btu/Hr used is less than the maximum Btu/Hr the space can support, the space is an un- confined space. You will need no additional fresh air ventilation.

WARNING:Iftheareainwhich the heater may be operated is smaller than that defined as an unconfined space or if the building is of unusually tight construction, provide adequate combustion and ventilation air by one of the methods described in the National Fuel Gas Code, ANSI Z223.1/NFPA54 Section 5.3 or applicable local codes.

VENTILATION AIR

Ventilation Air From Inside Building

This fresh air would come from an adjoining un- confined space. When ventilating to an adjoining unconfined space, you must provide two perma- nent openings: one within 12" of the ceiling and one within 12" of the floor on the wall connecting the two spaces (see options 1 and 2, Figure 2). You can also remove door into adjoining room (see option 3, Figure 2). Follow the National Fuel Gas Code, ANSI Z223.1/NFPA 54, Section 5.3, Air for Combustion and Ventilation for required size of ventilation grills or ducts.

12"

Figure 2 - Ventilation Air from Inside

Building

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, ANSI Z223.1/NFPA 54, 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.

	Outlet	Ventilated
		Attic
	Air
Outlet
Air		To Attic
		To
		Crawl
Inlet		Space
Air
	Inlet Air	Ventilated
		Crawl Space

Figure 3 - Ventila tion Air from Outdoors

113183-01A www.desatech.com 7