Alternate vent/flue location (upflow or horizontal left)

What is going on

The alternate vent exit is the large hole in line with the induced draft blower outlet. It is not available on counterflow models.

Likely causes

• Vent pipe condensate entering the draft inducer housing in horizontal left installs

Check in this order

1. Remove the four screws from the vent pipe flange on top of the furnace.
2. Remove the internal elbow and vent pipe.
3. Cut 2 1/2 in. from the flange.
4. Remove the plastic plug in line with the inducer outlet.
5. Install the cut flange section and connect it to the inducer with the supplied rubber coupling.
6. Reinstall the flange with the screws removed in step 1.
7. In horizontal left, provide condensate collection so vent condensate does not enter the inducer housing. If the vent drain elbow is removed, use an RF000142 kit.
8. Do not damage internal wiring or components when reinstalling the coupling and screws.

More furnace guides

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• Blower motor does not have enough information, fails to start 40 consecutive times