The furnace flue
What if my chimney vents a furnace?
The furnace flue is used to vent furnaces for gas and oil. High efficiency furnaces do not waste energy by sending heat up the chimney. As a result, temperatures in the flue drop low enough to produce condensation. The condensation combines with acids in the flue to create a damaging acidic moisture.
Understanding and maintaining your High Efficiency Furnace
Clay liners are particularly vulnerable to this acidic moisture assault.
Signs to look for of a deteriorating flue:
Flaking plaster and/or peeling wallpaper.
Staining on wall surfaces due to moisture.
Excessive moisture in gas or oil flues.
Excessive soot with oil furnace use.
Deterioration of the chimney structure.
Eroded or missing clay liner.
Carbon monoxide leaking into the home.
Joints between the tiles are not sealed.
I Want to Prevent all of These Problems
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