troubleshooting intermittent fuel fumes

mwhoyle

Hello, my folks have an oil furnace which provides supplemental heat to a wood stove. We've had 3 incidents in the last couple weeks of fumes suddenly "appearing" in the air around the furnace in the basement and then moving upstairs in to the house. The furnace is vented via the chimney which also vents the woodstove, and there's a butterfly valve on the furnace piping where the fuel fumes are coming from, I think. (It's like it's burping.)

A local furnace tech came out and inspected everything and did not find any leaks, but it's happened again twice since he came. He had replaced the burner nozzle in the furnace just as precaution/preventive-maintenance.

Anyone have any suggestions on resolving this? I don't ever recall this happening before in the 50 years they've lived there.

JStar

You need a competent tech to look at the system. Where are you located?

Jamie Hall

Does the furnace vent into the same flue as the wood stove? Or is it separate flues in the same chimney? If it's the former, that's a recipe for disaster.

mwhoyle

I think it must vent into a separate one, Jamie. And we're in western NC, US.

Jamie Hall

Under what conditions does this happen? The most likely problem is that the house is moderately to fairly tight, and that under some conditions there simply isn't enough air getting into the house -- or boiler room. That would be the first thing I would look at.