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So leaning to replace furnace and debating how high tech to go. Better efficiency and complexity or replace with like kind?
House was built in 1963 current unit installed in 1996 along with AC. We have no plans to move so may be here another 20 years.
Starting to get quotes.
Oh....northern PA, it was 7 degrees this morn but now up to 30 and sunny. And have two ventless log sets as backup heat.
AC: If is still working, I'd probably leave it alone. I'd imagine you run it for about 4 months of the year in N. PA, and it might last a long time. Given that use, it could be a long time before the greater efficiency paid for the replacement.
Furnace: Here's a site with some equipment options and prices, just to give you an idea. 80% furnaces are still sold, and (if they are allowed in your area) then they'll have the lowest installation costs since your existing flue can be used without modification and there's no need to run a condensate line. The newer 93%+ "condensing" units are more efficient so will save you money on natural gas, but they are more complex and are likely to be more trouble than an 80% unit. The condensing units are more popular than the 80% units, but do the math using your gas bill (and estimated future gas prices) to see if it is worth it to you.