Vent/Flue Pipe Cuts, Counterflow units

STANDARD FURNACE CONNECTIONS

It is the responsibility of the installer to ensure that the piping connections to the furnace are secure, airtight, and adequately supported.

As shipped, attachment “couplings” for vent/flue and combustion air intake pipe connections are provided on the furnace’s top cover (upflow) or basepan (counterflow). To use the standard connec- tions, field supplied vent/flue pipe and combustion air intake pipe (when applicable) should be secured directly to the furnace at these locations.

VENT/FLUE PIPE

Vent/flue pipe can be secured to the vent/flue coupling using the rubber coupling and worm gear hose clamps provided with this furnace (see “Standard Connections” figure). The rubber coupling allows separation of the vent/flue pipe from the furnace during servicing. NOTE: Do not use other commercially available “no hub connectors” due to possible material conflicts. The vent/flue pipe can also be secured using a PVC or ABS elbow or coupling using the appropriate glue (see Section IX, Materials and Joining Meth- ods.

NOTE: For non-direct vent installations, a minimum of one 90° elbow should be installed on the combustion air intake coupling to guard against inadvertent blockage.

COMBUSTION AIR PIPE

DIRECT VENT INSTALLATIONS

On upflow units secure the combustion air intake pipe directly to the air intake coupling. On counterflow units secure the combus- tion air intake pipe to the air intake coupling using the rubber cou- pling and worm gear hose clamps provided with the unit. The counterflow rubber coupling allows service removal of air intake piping internal to the furnace blower compartment. NOTE: Be- cause of probable material conflicts, do not use other commer- cially available “no hub connectors”. The combustion air intake pipe can also be secured directly to the counterflow unit air intake pipe coupling.

NON-DIRECT VENT INSTALLATIONS

A minimum of one 90° elbow should be installed on the combus- tion air intake “coupling” to guard against inadvertent blockage.

COMBUSTION				COMBUSTION	VENT/FLUE
COMBUSTION	VENT/FLUE			AIR PIPE	VENT/FLUE
AIR PIPE	VENT/FLUE			AIR PIPE	PIPE
AIR PIPE		PIPE		(DIRECT VENT ONLY)	PIPE
(DIRECT VENT ONLY)		PIPE		(DIRECT VENT ONLY)
(DIRECT VENT ONLY)
90 PVC	RUBBER		90 PVC	RUBBER
ELBOW	COUPLING		ELBOW	COUPLINGS
(NON-DIRECT VENT)	WITH WORM		(NON-DIRECT VENT)	WITH WORM
	GEAR CLAMPS			GEAR CLAMPS

NOTE: Standard and alternate locations can be combined (i.e., an installation may use the standard combustion air intake location but use the alternate vent/flue location or vice versa), if needed.

WARNING

EDGES OF SHEET METAL HOLES MAY BE SHARP. USE GLOVES AS A PRE- CAUTION WHEN REMOVING HOLE PLUGS.

ALTERNATE VENT/FLUE LOCATION

The alternate vent/flue location is the large hole directly in line with the induced draft blower outlet. To use the alternate vent/flue loca- tion refer to the following steps, the “Vent/Flue Pipe Cuts” figure, and the “Alternate Vent/Flue Location” figure.

NOTE: Counterflow instructions follow the upflow instructions.

1.Remove and save the four screws securing the vent/flue coupling to the furnace top panel.

Counterflow units.

Remove and save the four screws securing the vent/flue coupling to the furnace basepan. Also remove the three screws securing the furnace’s internal vent/flue piping to the blower deck.

2.Upflow and Counterflow units.

Loosen the worm gear hose clamps on the rubber elbow and detach it from both the induced draft blower and the vent/flue pipe.

3.Upflow and Counterflow units.

Remove the vent/flue pipe from the furnace.

4.Cut the vent/flue pipe 3.75 inches from the flanged end of the pipe. See Vent/Flue Pipe Cuts figure. The section of pipe attached to the coupling will reach through the side panel to the induced draft blower. Discard remaining pipe and elbows.

Counterflow units.

Cut the vent/flue pipe 3.75 inches from the blower deck coupling. See Vent/Flue Pipe Cuts figure. Save vent/flue pipe attached to blower deck coupling for use in the alternate location. Discard remaining pipe and elbows.

FLANGE

3.75"

CUT HERE

UPFLOW

COUNTERFLOW

STANDARD CONNECTIONS

Standard Connections

ALTERNATE FURNACE CONNECTIONS

If the standard locations are undesirable for a specific installation, alternate side panel locations are available for both combustion air inlet and vent/flue pipe connections. These locations may be of particular benefit to upright upflow installations requiring additional access to an A coil, or to upright counterflow installations requiring additional access to a filter or electronic air cleaner, or to horizontal installations desiring vent/flue (and combustion air intake) piping run vertically from the side of the cabinet.