Vent Clearances And Framing; Pipe Clearances To Combustibles; Wall Penetration Framing - Heatilator ND3933 Owner's Manual

6 6

Vent Clearances and Framing

A. Pipe Clearances to Combustibles
WARNING
Fire Risk
Explosion Risk
Maintain vent clearance to combustibles as
specifi ed.
• Do not pack air space with insulation or
other materials.
Failure to keep insulation or other materials
away from vent pipe may cause fi re.
(76 mm)
Drywall
1 in. (25 mm)
2 x 4 or
2 x 6
header
Figure 6.1 Minimum Top Vented DV Pipe Clearances
B. Wall Penetration Framing
• Wherever a combustible wall is penetrated, the hole must
be framed with a wall shield fi restop. This shield maintains
minimum clearances and restricts cold air infi ltration.
• If the wall being penetrated is of noncombustible materials
(material which will not ignite or burn, or has a UL fi re rating
of zero), a 9 in. (229 mm) diameter hole is acceptable.
• Whenever a wall is penetrated the wall shield fi restop
is only required on one side and no heat shield is
necessary.
• If your local inspector requires the wall shield fi restop on
both sides of the wall, then both wall shield fi restops must
have a heat shield attached to them.
24
3 in.
Air space clearances
to bottom and sides
of horizontal pipe
must be at least
1 in. (25 mm)
No combustible
framing to be
located within
shaded area.
1/2 in. (13 mm)
minimum to
perpendicular
wall.
Heatilator • Novus DV • 4031-550 Rev G • 11/07
Note: Heat shields MUST overlap by a minimum of 1-1/2 in.
(38 mm). The heat shield is 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. (102 mm) the existing heat shields must be
field trimmed. If wall thickness is greater than 7-1/4 in. (184
mm) a DVP-HSM-B will be required.
Heat
Shield
Figure 6.2 Minimum Horizontal Venting Clearances to Combus-
tible Materials
12 in.
The center of the
framing hole is
1 in. (25mm) above
the center of the
horizontal vent pipe.
Framing should be
constructed of 2 X 4
lumber or heavier.
Model
ND3630
ND3933
ND4236
ND4842
Figure 6.3 Exterior Wall Hole
3 in. (76 mm)
top clearance
Heat
Shield
1 in. (25 mm)
Wall
clearance
Shield
bottom & sides
Firestop
WALL
10 in.
Vent framing hole.
DO NOT PACK WITH
INSULATION OR
OTHER MATERIAL.
D*
E*
* To center of pipe.
D
Top Vent Rear Vent
in. 39-1/2 23-1/2
mm 1003
E
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