A version of this story ran in 2018. It returns to the Monitor’s online most-read list during every cold snap, so what the heck, here’s an updated version.
There’s an option for homeowners who run out of heating oil and can’t wait for a refill, or who can’t afford to pay the 150-gallon minimum to get a delivery: diesel fuel.
Diesel sold at gas stations is an acceptable replacement for home heating oil in virtually all furnaces. This should only be a short-term option, though. Running on diesel for too many days can interfere with the operation of the furnace.
Most home heating oil is the type known as No. 2, a designation that indicates weight and grade. It and diesel are midlevel or midweight distillations of petroleum. They produce roughly the same amount of heat and can be burned by the same systems.
As it currently stands, cost won’t be much different. Both diesel and heating oil are around $3.20 a gallon. Diesel includes a road tax, while heating oil doesn’t.
Kerosene is another acceptable alternative to home heating oil. It tends to be more expensive, however: Currently it’s about $3.90 a gallon.
Gasoline, on the other hand, cannot be used as a substitute for heating oil, as it is a lightweight distillation of petroleum, a very different type of molecule. Do not put ordinary gasoline in your oil tank – it will damage your furnace and cause other problems.
It’s recommended that you turn off your furnace before pouring the diesel into your heating oil tank, then wait 10 minutes or so before turning the furnace back on. This will allow any sediment that was stirred up in the tank to settle, making it less likely to clog the system.
One final note: It is not a good idea to make the diesel-for-oil substitution in the other direction. Home heating oil is not a good replacement for diesel in vehicles because it lacks lubrication aspects that are important for engines to operate.