roof vent for furnace

Problems related to residential installations.

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roof vent for furnace

Post by MIKEMCD77 » Tue Dec 19, 2017 6:27 pm

I have a 6" diameter roof vent for my gas furnace. I want to replace the vent. Is it OK to replace it with a 4" diameter vent? Here is the info on my -

XE-90 gas furnace; Trane (American Standard) “high efficiency.”
Mine is a Downflow and “NON-direct vent”; 74,000 BTUH capacity output; ICS (AFUE) 91.0
Furnace model # TDC080C942B4

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- roof vent for furnace

Post by Freon » Sun Dec 31, 2017 10:19 am

You really need to refer to the installation manual. However you can get an idea by looking at the diameter of the diameter of the vent at the furnace where you'd connect continuing vent pipe. If at the furnace it's 4" take-off then I would THINK a 4" vent world be okay. You can try it and CAREFULLY AND CONTINUOUSLY monitor that all functions perfectly. But the installation manual is your best source for the correct answer.

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