Most heating up North East in Main NH and Vermont is by Propane (tanked), Methane (Natural Gas in street) or HHO#2.
I hate diesel fumes too. Smelling it depend on the weather. There is no smell in the basement near the Boiler . The burner on the boiler was running too much excess air, I added a touch extra of fuel pressure it seems to be doing better.
You should have 0 to trace smoke on an oil burner. They test with a white gauze disc using a draw pump, pulling from the flue through a bung hole. they
should also check CO, CO2, O2 using a Testo combustion analyser and probe. Old guys set it to factory table specs for the burner then tweek by eye, I have seen.
At least Diesel doesn't blow up your house if it has a malfunction like Natural Gas does.
This happened just 5 miles from me ...
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