48
Installing the Vent Pipe Adapter and Combustion Air
Pipe Adapter
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in personal
injury or death.
To route the vent pipe and combustion air pipe through the
furnace, the manufacturer supplied kit must be used. Failure
to properly seal the blower compartment from the furnace
vestibule could result in the circulation of carbon monoxide
throughout the structure. The vent pipe and combustion air
pipe must be a continuous pipe while passing through the
blower compartment. Seals supplied in this kit must be
installed per the instructions provided. Follow all
procedures outlined in these instructions.
WARNING
!
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in personal injury
or death.
DO NOT
use cement to join polypropylene venting systems.
Follow the polypropylene venting system manufacturer’s
instructions for installing polypropylene venting systems.
!
WARNING
NOTE
: The rubber coupling that attaches to the vent pipe adapter
must be used. The adapter seals the vent pipe to the casing and
reduces the strain on the vent elbow attached to the inducer.
1. Apply the gaskets to the vent pipe and combustion air pipe
adapters. If supplied, remove and discard round center
“slug” from interior of gasket. See Fig. 44.
NOTE
: The vent pipe adapter can be distinguished from the inlet
pipe adapter by the absence of an internal pipe--stopping ring. The
vent pipe can pass through the vent pipe adapter; it cannot pass
through the inlet pipe adapter.
Attach gaskets to vent pipe and
combustion air adapters.
Vent Coupling and Adapter
A13074
Fig. 44 -- Vent Coupling and Adapter with Gaskets
2. Align the screw holes in the plastic vent pipe adapter with
the dimples in the casing.
3. Pilot drill the screw holes for the adapter in the casing and
attach the vent pipe adapter to the furnace with sheet metal
screws
4. Slide the end of the rubber vent coupling with notches in it
over the standoffs on the vent pipe adapter.
5. Insert a length of vent pipe through the coupling into the
outlet of the vent elbow.
6. Tighten the clamp around the outlet of the vent elbow.
Torque the clamp to 15 lb--in.
The following instructions are for PVC/ABS DWV vent
piping only. DO NOT USE THESE TECHNIQUES FOR
POLYPROPYLENE VENT PIPING SYSTEMS. See the
polypropylene vent system manufacturer’s instructions for
installing polypropylene venting systems.
NOTICE
Install the remaining vent and combustion air pipes as shown
below. It is recommended that all pipes be cut, prepared, and
preassembled before permanently cementing any joint.
1. Working from furnace to outside, cut pipe to required
length(s).
2. De--burr inside and outside of pipe.
3. Chamfer outside edge of pipe for better distribution of
primer and cement.
4. Clean and dry all surfaces to be joined.
5. Check dry fit of pipe and mark insertion depth on pipe.
6. Insert the vent pipe into the vent elbow.
7. Torque clamp on vent elbow 15 lb--in.
8. Torque clamp on vent coupling 15 lb--in.
9. Insert the combustion air pipe into the adapter.
10. Pilot drill a screw hole through the adapter into the com-
bustion air pipe and secure the pipe to the adapter with
sheet metal screws.
DO NOT DRILL INTO
POLYPROPYLENE VENT PIPES. Use an optional acces-
sory vent coupling, if needed.
11. Seal around the combustion air pipe with silicone or foil
tape. SILICONE SEALERS MAY NOT BE APPROPRI-
ATE FOR POLYPROPYLENE VENT SYSTEMS. SEE
POLYPROPYLENE VENT SYSTEM MANUFACTUR-
ER’S INSTRUCTIONS.
12. After pipes have been cut and preassembled, apply gener-
ous layer of cement primer to pipe fitting socket and end of
pipe to insertion mark. Quickly apply approved cement to
