| MORE HEAT EXCHANGER SURFACE MEANS LESS HEAT UP THE CHIMNEY |
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This 8-inch diameter type 304 Stainless Steel secondary heat exchanger recovers heat that would normally go out the chimney. This added surface plus the large firebox and massive primary heat exchanger provide a total of 82 square feet of heating surface compared to 30-35 square feet on a comparable size oil or gas furnace.