Hearth and Home Technologies CNXT4842ILH Vent Clearances and Framing, Wall Penetration Framing

8 Vent Clearances and Framing

A. Pipe Clearances to Combustibles

WARNING! Risk of Fire! Maintain air space clearance to vent. DO NOT pack insulation or other combustibles:

•Between ceiling firestops

•Between wall shield firestops

•Around vent system

Failure to keep insulation or other material away from vent pipe may cause over heating and fire.

Note: Heat shields MUST overlap by a minimum of 1-1/2 in. (38 mm).

•DVP heat shield - designed to be used on a wall 4 in. to 7-1/4 in. (102 mm to 184

mm)thick.

•If wall thickness is less than 4 in. the existing heat shields must be field trimmed. If wall thickness is greater than 7-1/4 in. an extended heat shield will be required.

•SLP heat shield - designed to be used on a wall 4-3/8 in. to 7-5/8 in. (111 mm to 194 mm thick).

•If wall thickness is less than 4-3/8 the existing heat shields must be field trimmed. If wall thickness is greater than 7-5/8 in. an extended heat shield will be required.

(DVP Pipe Shown)

B. Wall Penetration Framing

Combustible Wall Penetration

Whenever a combustible wall is penetrated, you must frame a hole for the wall shield firestop(s). The wall shield firestop maintains minimum clearances and prevents cold air infiltration.

•The opening must be framed on all four sides using the same size framing materials as those used in the wall construction.

•SLP pipe - A wall shield firestop must be placed on each side of an interior wall. A minimum 1 1/2 in. (38 mm) overlap of attached heat shields must be maintained.

•DVP pipe - A wall shield firestop is required on one side only on interior walls. If your local inspector requires a wall shield firestop on both sides, then both wall shield firestops must have a heat shield attached to them.

•See Section 10.N. for information for regarding the installation of a horizontal termination cap.

3 in. (76 mm) top clearance

1 in. (25 mm) clearance around vertical sections

Heat

Shield

Wall

Shield

Firestop

3 in. (76 mm) top clearance *

Heat

Shield

1 in. (25 mm) clearance bottom & sides

Non-Combustible Wall Penetration

If the hole being penetrated is surrounded by noncombus- tible materials such as concrete, a hole with diameter one in. greater than the pipe is acceptable.

Whenever a non-combustible wall is penetrated, the wall shield firestop is only required on one side and no heat shield is necessary.

WALL

Heat

Shield

Wall

Shield

Firestop

3 in. (76 mm) top clearance *

Heat

Shield

1 in. (25 mm) clearance bottom & sides

	10 in.	Vent framing hole.
12 in.		DO NOT PACK WITH
		INSULATION OR OTHER

MATERIAL.

The center of the framing hole is

1 in. (25mm) above the center of the horizontal vent pipe.

WALL

* When using SLP pipe, minimum clearances from the vent pipe to combustible materi-

als at inside wall firestops are:Top: 2-1/2 in. (64 mm) Bottom: 1/2 in. (13 mm) Sides: 1 in. (25 mm)

Figure 8.1 Horizontal Venting Clearances To Combustible Materi- als

A*

B*

Framing should be constructed of 2 X 4 lumber or heavier.

*Measured to center of pipe.

		A	B
Model		Top Vent	Rear Vent
CNXT4236	inches	42 1/4	27 1/4
	mm	1073	692
CNXT4842	inches	48 1/4	27 1/4
	mm	1226	692

Figure 8.2 Wall Penetration

34 Heatilator • Caliber CNXT Series • 4047-132 Rev U • 11/08