Existing Venting Systems
When an existing furnace is removed or replaced, the original
venting system may no longer be sized to properly vent the
attached appliances. An improperly sized venting system can
result in spillage of flue products into the living space, the
formation of condensate, leakage, etc. See the "Carbon
Monoxide Poisoning Hazard" for proper test procedure.
CARBON MONOXIDE POISONING HAZARD
Failure to follow the steps outlined below for each
appliance connected to the venting system being
placed into operation could result in carbon monoxide
poisoning or death.
The following steps shall be followed for each appliance
connected to the venting system being placed into operation,
while all other appliances connected to the venting system are
not in operation:
1. Seal any unused openings in the venting system.
2. Inspect the venting system for proper size and horizontal
pitch, as required in the National Fuel Gas Code,
ANSI Z223.1/NFPA 54 or the CSA B149.1, Natural Gas and
Propane Installation Codes and these instructions.
Determine that there is no blockage or restriction, leakage,
corrosion and other deficiencies which could cause an
3. As far as practical, close all building doors and windows
and all doors between the space in which the appliance(s)
connected to the venting system are located and other
spaces of the building.
4. Close fireplace dampers.
5. Turn on clothes dryers and any appliance not connected to
the venting system. Turn on any exhaust fans, such as
range hoods and bathroom exhausts, so they are operating
at maximum speed. Do not operate a summer exhaust fan.
6. Follow the lighting instructions. Place the appliance being
inspected into operation. Adjust the thermostat so
appliance is operating continuously.
7. Test for spillage from draft hood equipped appliances at the
draft hood relief opening after 5 minutes of main burner
operation. Use the flame of a match or candle.
8. If improper venting is observed during any of the above
tests, the venting system must be corrected in accordance
with the National Fuel Gas Code, ANSI Z223.1/NFPA 54
and/or CSA B149.1, Natural Gas and Propane Installation
9. After it has been determined that each appliance connected
to the venting system properly vents when tested as
outlined above, return doors, windows, exhaust fans,
fireplace dampers and any other gas-fired burning
appliance to their previous conditions of use.
1. Run venting to the furnace, see "Plan Vent System."
2. Attach the air intake pipe to the furnace connector.
Use high temperature RTV silicone sealant to attach the air
intake pipe into the connector on the burner box so the air
intake pipe can be removed if service is required.
NOTE: Do not use cement.
3. For non-direct vent installations only, install the inlet air
restrictor plate in the air inlet pipe.
4. Attach the flue pipe connector to the furnace.
5. For both direct and non-direct vent installations, install the
flue pipe screen at the outside end of the flue pipe.
6. Make sure all vent connections do not leak.
7. Check that the exhaust vent pipe terminates outside the
8. Prime the trap system by slowly pouring 1 cup of water down
the vent pipe. The vent pipe on horizontal runs must slope
upward, away from the furnace, at a minimum pitch of ¹⁄₄ in.
per foot of run, to prevent accumulation of condensate.
NOTE: On initial start-up of the unit, some of the water used
to prime the trap system may run down into the combustion
blower and cause noise.
Install Condensate Disposal
IMPORTANT: The condensate drain should be routed directly to
a locally acceptable disposal area. The condensate drain line
should not be run directly to the outdoors especially in colder
climates where temperatures may cause the condensate to
freeze in the drain line.
1. Connect the ¹⁄₂ in. NPT x ³⁄₄ in. PVC adapter (supplied) in the
drain on the side that the draining will occur.
NOTE: The condensate can be drained from either the right
or left side of the furnace.
2. Connect the plastic pipe plug opposite of the drain.
3. Connect ³⁄₄ in. PVC pipe, make a connection from the adapter
just installed to extend just outside the unit. Install a ³⁄₄ in.
PVC tee as shown.
4. From the tee, connect the drain to the disposal area.
NOTE: The top of the tee must be left open for proper
condensate drainage. The open end of the tee must be
oriented so that the condensate does not run out of this
in. NPT plug
3. Tee (must remain open)