I recently had an issue with an oil furnace blower that wouldn’t switch off, and the constant operation resulted in excessively high energy bills.
I was concerned about the heating plan quitting for real and not lasting as long due to wear and tear; I hoped that by googling the concern and fixing it myself, I might avoid an extravagant repair bill from a professional… Online, more than 2 articles commanded that the temperature control settings might be the problem.
The temperature control talks to the oil furnace when to turn on or off. I first verified that the fan setting was set to AUTO rather than ON. In the ON position the blower is told to run non stop. In the AUTO setting, it only functions when the oil furnace is producing heat. I also checked that the temperature wasn’t set overly high, forcing the oil furnace to keep working in order to achieve it! Since I kept the temperature control set at around 69 degrees, I didn’t think this could be the issue. The next opportunity was the fan limit switch, located under the oil furnace hood. I doubted that this concealed switch somehow got adjusted to MANUAL or ON but checked it anyway. I needed to remove the panel to locate the switch. I tried resetting it, hoping this would make a difference, however it didn’t. I had no clue but to contact an Heating and A/C company and schedule a repair, but happily, I was able to get an appointment for the following day. The professional was tied up to arrive anytime while in an eight-hour window, which meant taking a day off from my job. I was honestly excited when I got a call in the day with an approximate ETA and the professional showed up right on time!