I just replace my roof this fall. I’m noticing staining around the metal vent for my oil fired furnace. The metal vent is in good condition with no rust. Any idea what would cause the staining of my new roof?
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Haven't heated with oil in 25 yrs
and then I can't remember any roof staining.
But, how about a dirty burning furnace-when you burn lamp oil in a lamp and the wick is too high, plenty of soot is produced-which coats the glass.
How old is the furnace? and when was it serviced last?
IIncomplete combustion due to
Incomplete combustion due to imporper air/fuel mixture may be causing soot buildup in the flue. What doesn't stick to the flue or chimney goes out the top and condenses when it mixes with cold air. Joints in the flue can also leak grimy soot.
Have a qualified serviceman who's experienced in oil furnaces check this out. If he knows what he's doing, he will have and know how to use a combustion analyzer which has a probe that he inserts into the flue to measure excess oxygen, excess carbon monoxide, carbon dioxide, and temperature. Ask about this before you spend any money on an unqualified technician.