Nordyne RC 92+, RL 90+ installation instructions Equipment in a Confined

Vent or

Chimney

Each opening to outside must be at least 1 sq. in. per 4000 Btuh of total input rating.

-	12"
	Max
		Furnace
-
12" Max		Water Heater

	Minimum
Total Input	Free Area	Round Duct
Rating (Btuh)	(Each Opening)	Diameter
40,000	10 sq. in.	4"
60,000	15 sq. in.	5"
80,000	20 sq. in.	5"
100,000	25 sq. in.	6"
120,000	30 sq. in.	6"
140,000	35 sq. in.	7"
160,000	40 sq. in.	8"

Figure 12. Equipment in a Confined Space with all Combustion Air drawn from Out- doors through Exterior Wall

Ventilation Louvers at each end of attic

	Vent or
	Chimney
	Ventilation Louvers
	(each end of attic)
	-
	Outlet	NOTE: Air open-
	Air	ings shall each
	Water	have a free area
Furnace		of not less than
	Heater	one square inch
		per 4,000 Btuh of
Alternate		the total input rat-
	Inlet Air	ing of all equipment
Air Inlet		in the enclosure.
	-
	-	-

Ventilation Louvers For

Unheated Crawl Space

Figure 14. Equipment in a Confined Space with all Combustion Air drawn from Out- doors through Ventilated Crawl Space and Ventilated Attic

Vent or

Chimney

Vent or

Chimney

Attic

Insulation

Furnace

Water Heater

Air Duct must be at least 1 sq. in. per 4,000 Btuh of total input rating.

Ducts must extend above attic insulation.

Air Duct must be at least 1 sq. in. per 4,000 Btuh of total input rating.

12" Max

Air Duct	Air Duct
	must be
Furnace	at least
	1 sq. in.
	per 2000
	Btuh of
Air Duct	total input
	rating.
Water Heater

	Minimum
Total Input	Free Area	Round Duct
Rating (Btuh)	(Each Opening)	Diameter
40,000	10 sq. in.	4"
60,000	15 sq. in.	5"
80,000	20 sq. in.	5"
100,000	25 sq. in.	6"
120,000	30 sq. in.	6"
140,000	35 sq. in.	7"
160,000	40 sq. in.	8"

	Minimum
Total Input	Free Area	Round Duct
Rating (Btuh)	(Each Opening)	Diameter
40,000	20 sq. in.	5"
60,000	30 sq. in.	6"
80,000	40 sq. in.	7"
100,000	50 sq. in.	8"
120,000	60 sq. in.	9"
140,000	70 sq. in.	10"
160,000	80 sq. in.	10"

Figure 13. Equipment in a Confined	Figure 15. Equipment in a Confined Space
Space with all Combustion Air drawn from	with all Combustion Air Drawn from the
Outdoors through Vertical Ducts – from	Outside through Horizontal Ducts
Ventilated Attic

15