York Comprehensive Guide for DFAH Burners by - Installation and Maintenance

107272-UIM-B-1105

A

Single trunk duct

C

Transition Duct with Branches

B*	Transition duct
Dual trunk duct with crossover connector
1

Dual trunk duct	4
	2
	Crossover

Branches

3

1.Crossover Duct must be centered directly under furnace.

2.Use 12” (30.5 cm) Diameter Round or insulated Flex-duct only.

3.Terminate Flex-duct (opposite furnace) in the center of the trunk duct.

4.Flex-duct material must be pulled tight — No Loops or unnecessary dips — Air Flow may be impeded.

FIGURE 3: Air Distribution Systems

				Furnace to Closet Door Clearance —
Return Air Grille Part No.				5 Inches (12.7 cm) or more
7900-287P/A * White				The closet door MUST have a minimum of 250 Inches2(1613 cm2)
				of free area in the upper half of the door.
				If opening for return air is located in the floor or sidewalls and
				below the top of the furnace casing:
A				1. 6 inches (15.2 cm) minimum clearance must be provided on side
250 IN.	2	2	)	where return is located, and
		(161 cm		2. 6 inches (15.2 cm) minimum clearance must be maintained from
MINIMUM			B
FREE AREA				the front of furnace.
			250 IN.2 (161 cm2)
50 IN.2 (322 cm2)			MINIMUM	CLOSET
			FREE AREA	FURNACE
MINIMUM
FREE AREA					5 in (12.7 cm) or greater * Closet
					to Door Clearance
					Return Air Closet Door Part No.
				DOOR	7900-7771/C* White

FIGURE 4: Closet To Door Clearance - 5” or Greater

250 IN.2 (161 cm2)
MINIMUM
FREE AREA	B
50 IN.2 (322 cm2)
MINIMUM
FREE AREA

As an option to the lower grill, an undercut of 2-1/2" will provide 50 inches2 (322 cm2) of free area.

Furnace to Closet Door Clearance —

Greater than 1 Inch (2.54 cm) and Up to 5 (12.7 cm) Inches

1.The closet door MUST have a minimum of 250 Inches2 (1613 cm2) of free area in the upper half of the door and a minimum of 50 Inches2 (322 cm2) of free area in the lower area of the door. The lower closet door grille may be omitted if an undercut of 2-1/2 inches (16.1 cm) is provided in the door.

2.A fully louvered closet door MUST have a minimum of

250 Inches2 (1613 cm2) of free area in the upper half of the door.

250IN.2 (161cm2)

MINIMUM FREE AREA

FIGURE 5: Furnace To Closet Door Clearance - 1” To 5”

250IN.2 (161 cm2)

MINIMUM FREE AREA

50IN.2 (322 cm2)

MINIMUM FREE AREA

Furnace to Closet Door Clearance —

Less than 1 Inch (2.54 cm)

The closet door MUST have three return air grilles. The total free area of the two upper grilles must be minimum of 250 Inches2 (1613 cm2) . The total free area of the lower grille MUST be a minimum of 50 Inches2 (322 cm2).

The grilles MUST BE ALIGNED directly opposite the return air grille of the furnace door.

FIGURE 6: Furnace To Closet Door Clearance - Less Than 1”

Unitary Products Group 7