Bryant 340MAV DuctFlanges, Ii. Ductwork Acoustical Treatment, CrawlspaceHorizontal Application

PERFORATED

DISCHARGE DUCT

FLANGE

NO

YES

210°

MIN

YES

When a furnace is installed so that the supply ducts carry air circulated by the furnace to areas outside the space containing the furnace, the return air shall also be handled by a duct(s) sealed to the furnace casing and terminating outside the space containing the furnace.

Secure ductwork with proper fasteners for type of ductwork used. Seal supply- and return-duct connections to furnace with code approved tape or duct sealer.

Flexible connections should be used between ductwork and furnace to prevent transmission of vibration. Ductwork passing through unconditioned space should be insulated to enhance system performance. When air conditioning is used, a vapor barrier is recommended.

Maintain a 1-in. clearance from combustible materials to supply air ductwork for a distance of 36 in. horizontally from the furnace. See NFPA 90B or local code for further requirements.

Fig. 21—Duct Flanges

A93029

For a furnace not equipped with a cooling coil, the outlet duct shall be provided with a removable access panel. This opening shall be accessible when the furnace is installed and shall be of such a size that the heat exchanger can be viewed for possible openings using light assistance or a probe can be inserted for sampling the air

Air Conditioning Contractors National Association (SMACNA) or American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) or consult The Air Systems Design Guide- lines reference tables available from your local distributor. The duct system should be sized to handle the required system design CFM at the design static pressure.

stream. The cover attachment shall prevent leaks.

II. DUCTWORK ACOUSTICAL TREATMENT

Metal duct systems that do not have a 90 degree elbow and 10 ft of main duct to the first branch take-off may require internal acoustical lining. As an alternative, fibrous ductwork may be used

3⁄8-IN. ROD

ANGLE

IRON OR

EQUIVALENT

	(B)
	(A)
(B)
(A) ROD LOCATION
USING DIMPLE
LOCATORS	3/8-IN. HEX NUT	(A)
(SEE DIMENSIONAL
DWG FOR	& WASHER (4)
LOCATIONS)	REQD PER ROD

53⁄4″

ALTERNATE SUPPORT LOCATION 4-IN. MIN 8-IN. MAX

DRAIN

(A)

(B)

13/16-IN. MAX

(B)ALTERNATE SUPPORT LOCATION FROM BACK

(A)PREFERRED ROD LOCATION

(B)ALTERNATE ROD LOCATION

NOTES: 1. A 1 In. clearance minimum between top of furnace and combustible material.

2.The entire length of furnace must be supported when furnace is used in horizontal position to ensure proper drainage.

A93304

Fig. 22—Crawlspace Horizontal Application

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