Heatilator • Caliber CD Series • 4040-263 Rev M • 06/08
18
Combustible flooring may be installed next
to the front of the appliance.
C
B
A
1/2 in. (13 mm)
1/2 in.
(13 mm)
Drywall
0 in.
30 in.
(762 mm)
to ceiling
D
0 in. to
floor
0 in. to level
of standoffs
Combustible Object
36 in.
(914 mm)
B. Construct the Appliance Chase
A chase is a vertical box-like structure built to enclose the
gas appliance and/or its vent system. In cooler climates
the vent should enclosed inside the chase.
NOTICE:
Treatment of ceiling
fi
restops and wall shield
fi
restops and construction of the chase may vary with the
type of building. These instructions are not substitutes for the
requirements of local building codes. Therefore, you MUST
check local building codes to determine the requirements
to these steps.
Chases should be constructed in the manner of all out-
side walls of the home to prevent cold air drafting prob-
lems. The chase should not break the outside building
envelope in any manner.
Walls, ceiling, base plate and cantilever
fl
oor of the chase
should be insulated. Vapor and air in
fi
ltration barriers
should be installed in the chase as per regional codes for
the rest of the home. Additionally, in regions where cold
air in
fi
ltration may be an issue, the inside surfaces may
be sheetrocked and taped for maximum air tightness.
Figure 5.2 Clearances to Combustibles
C. Clearances
NOTICE:
Install appliance on hard metal or wood surfaces
extending full width and depth.
DO NOT
install directly on
carpeting, vinyl, tile or any combustible material other than
wood.
WARNING! Risk of Fire!
Maintain speci
fi
ed air space
clearances to appliance and vent pipe:
• Insulation and other materials must be secured to
prevent accidental contact.
• Failure to maintain airspace may cause overheating and
a
fi
re.
To further prevent drafts, the wall shield and ceiling
fi
re-
stops should be caulked with high temperature caulk to
seal gaps. Gas line holes and other openings should be
caulked with high temp caulk or stuffed with unfaced insu-
lation. If the appliance is being installed on a cement slab,
a layer of plywood may be placed underneath to prevent
conducting cold up into the room.
Model
A
Rough
Opening
(Width)
B
Rough
Opening
(Height)
C
Rough
Opening
(Depth)
D
Rough
Opening
(DVP Pipe)
D
Rough Open-
ing (SLP
Pipe)
CD4236
in.
42
39
23
10
9
mm
1067
984
584
254
229
CD4842
in.
48
39
23
10
9
mm
1219
984
584
254
229
Note:
Adjust framing dimensions for interior sheathing (such
as sheetrock)
