Desa CB36P, CB36N operation manual Venting Installation

VENTING INSTALLATION

Continued

In each case the offsets must be supported and firestops must be positioned wherever the vent must pass through a sub-floor, ceil- ing joist or an attic overhang. The vent pipe must terminate vertically into a listed type vent cap and extend a sufficient height through an approved roof flashing, roof jack or a roof thimble. At all points the listed clearances must be maintained.

Vent terminations must be located in accor- dance with height and proximity rules of NFPA No. 54 or CAN/CSA B149. These rules apply to vents at 12" diameter or less and require a minimum height in accordance with the roof pitch and a minimum of 8 foot distance from a vertical wall or obstruction (see Figure 11).

If venting horizontally through a side wall be- comes necessary, a listed thimble approved for use with B-type vent must be used. Check with your local codes before venting through a side wall.

Some codes areas allow the use of existing B- type vent systems if the system is at or above the recommended diameter of the flue.

The flue connection must be made using listed B-type connectors and the existing system must be code inspected for damage and proper installation.

It is not recommended that this appliance be common vented with and existing gas burning appliance. However, if it becomes necessary to common vent the appliance. The venting system must be sized and configured in ac- cordance with the common venting guides Appendix G of the current National Fuel Gas Code NFPA No. 54/ANSI Z223.1 and in Canada with CAN/CSA B149.

Note: Before connecting this appliance to an existing vent system or a common venting system consult with your local architect plan- ner, or building official.

		Listed
		Vent Cap		Listed		Listed
				Vent Cap
						Vent Cap
	Maintain		Maintain
			Listed
	Listed		Clearance
	Clearance						Maintain
			Support Each	Maintain
							Listed
			Lateral At	Listed			Clearance
			Least Every	Clearance
		60	6 Feet	45
				12' Min.
8' Position						45°	10'
					Position
		6'
12' Min.	Firestop		Position	45	Firestop		12' Min.
			Firestop
		Maintain		Maintain			Maintain
		Listed		Listed			Listed
		Clearance		Clearance			Clearance

EXAMPLE 1	EXAMPLE 2	EXAMPLE 3
	Figure 10 - Typical B-Vent Configuration

Lowest Listed

Discharge Vent Cap

Opening

	8 Ft. Min.
Listed
Gas
Vent	12

H(Min) Height From Roof

	Roof Pitch	H (Min.)
	Flat to 6/12	1.0 ft (0.3 m)
	6/12 to 7/12	1.25 ft (0.38 m)
	Over 7/12 to 8/12	1.5 ft (0.46 m)
	Over 8/12 to 9/12	2.0 ft (0.61 m)
	Over 9/12 to 10/12	2.5 ft (0.76 m)
x	Over 10/12 to 11/12	3.25 ft (0.99 m)
Roof Pitch x/12	Over 11/12 to 12/12	4.0 ft (1.22 m)
	Over 12/12 to 14/12	5.0 ft (1.52 m)
Listed Clearance	Over 14/12 to 16/12	6.0 ft (1.83 m)
	Over 16/12 to 18/12	7.0 ft (2.13 m)
	Over 18/12 to 20/12	7.5 ft (2.27 m)
	Over 20/12 to 21/12	8.0 ft (2.44 m)

Figure 11 - B-Vent Termination

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