We do not smoke or have a fire place in our home. We have hot water- baseboard heat fueled by oil with a flute which exits out the basement wall from the boiler. We have had a burning, smokey smell over the last several weeks. We replaced the exhaust fan to the flute. No improvement in odor. What is causing this? Please help!

I'd call a technician... might set off 'smoke bomb' (not harmful) in ducts to find leak ? But tell your neighbors first !