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Heatilator • NNXT4236IF, NNXT4236ILF, NNXT3633IF, NNXT3633ILF Installation Manual • 4055-980 Rev. D • 9/15
24
A*
B*
10 in.
12 in.
C
D
10 in.
10 in.
10 in.
12 in.
A. Pipe Clearances to Combustibles
WARNING! Risk of Fire!
Maintain air space clearance
to vent.
DO NOT
pack insulation or other combustibles:
• Between ceiling
fi
restops
• Between wall shield
fi
restops
• Around vent system
Failure to keep insulation or other material away from
vent pipe could cause overheating and
fi
re.
5
5
Vent Clearances and Framing
Figure 5.2 Wall Penetration
* Shows center of vent framing hole for top or rear venting. The center of the
hole is one (1) in. (25.4 mm) above the center of the horizontal vent pipe.
Figure 5.1 Horizontal Venting Clearances To Combustible
Materials
A
B
DO NOT PACK WITH
INSULATION OR
OTHER MATERIAL.
* 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)
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
.
,IZDOOWKLFNQHVVLVOHVVWKDQLQWKHH[LVWLQJKHDWVKLHOGVPXVWEHILHOGWULPPHG,I
wall thickness is greater than 7-1/4 in. a DVP-HSM-B 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).
,IZDOOWKLFNQHVVLVOHVVWKDQWKHH[LVWLQJKHDWVKLHOGVPXVWEHILHOGWULPPHG
,IZDOOWKLFNQHVVLVJUHDWHUWKDQLQD'93+60%ZLOOEHUHTXLUHG
(DVP-SLP Pipe Shown)
3 in. (76 mm)
top clearance *
1 in. (25 mm)
clearance
bottom & sides
Heat
Shield
Wall
Shield
Firestop
Heat
Shield
WALL
3 in. (76 mm)
top clearance *
1 in. (25 mm)
clearance
bottom & sides
Heat
Shield
Wall
Shield
Firestop
Heat
Shield
WALL
3 in. (76 mm)
top clearance
1 in. (25 mm)
clearance around
vertical sections
A*
B*
C
D
Inches
40-1/2
24-1/2
39-1/2
23-1/2
B. Wall Penetration Framing/Firestops
Combustible Wall Penetration
Whenever a combustible wall is penetrated, you must
frame a hole for the wall shield
fi
restop(s). The wall shield
fi
restop maintains minimum clearances and prevents cold
air in
fi
ltration.
• 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
fi
restop 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
fi
restop is required on one side
only on interior walls. If your local inspector requires a
wall shield
fi
restop on both sides, then both wall shield
fi
restops must have a heat shield (refer to Section
12.A.) attached to them.
• See Section 7.F. for information for regarding the instal-
lation of a horizontal termination cap.
Non-Combustible Wall Penetration
If the hole being penetrated is surrounded by non-com-
bustible materials such as concrete, a hole with diameter
one inch greater than the pipe is acceptable.
Whenever a non-combustible wall is penetrated, the wall
shield
fi
restop is only required on one side and no heat
shield is necessary.