On Saturday, October 24, 2015 at 2:44:04 PM UTC-5, Gary wrote:
Our old Amana 92% after 20 yrs is still working good but they say we
should buy a new one at twice the price of the old one. For this kind of
money around $8000.00 they ought to last atleast 30 yrs! why can't they
make the heat exchangers better?
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If your furnace has a stainless steel heat exchanger, I'd keep it and have it checked for leakage every year at the start of heating season. I've never seen any stainless steel furnace parts fail due to corrosion. ヽ(ヅ)ノ

[8~{} Uncle Stainless Monster