Burner kicks on too much during a heating cycle....need advice
Had something similar during first winter in our recently bought house, oil burner on an ancient boiler cutting in and out, burner blower slamming the flue every time with a bang, and releasing a cloud of acrid smoke and soot into the basement, from where it spread elsewhere. Took 3 visits (thankfully all covered by maintenance contract) of cleaning the burner, replacing filters, etc etc to get it into some semblance of working - though we'd get an acrid whiff every time the thing kicked on.
I permanently solved the problem following summer by ripping the whole thing out, getting gas hooked up, and installing a new high-efficiency condensing gas boiler. It is compact, silent, no smells, no noisy truck coming to pump oil every few weeks, and bills are about one third of what they used to be.