We occasionally smelled smoke after work was done on the heating system. When asked to review the repair, I mentioned that we sometimes, but not always smelled smoke when the heater was running.
Ernesto was dispatched the next day and checked out the system. He determined that all was operating OK and that the smoke was probably from the new part that was installed, as they sometimes had oil on them when new from the factory. This residual oil could burn off after the first few run times and that was probably the source of the smell He could detect no odor at the furnace or in the room where we smelled it, so we believe the oil has all burned off and it should no longer be a problem. We will keep sniffing, but we thank Ernesto for his diagnosis and Beutler for his prompt response.