Can I Put Diesel Fuel in My Home Heating Oil Tank?

If you are getting low on heating oil, you may be wondering if diesel fuel can be used. Good news: diesel fuel and heating oil are nearly identical. In this post we will walk you through when it is appropriate to substitute diesel fuel for heating oil.

Add Diesel Fuel When You are Out Of Heating Oil

If you suddenly find that your house is cold or you have no hot water, you may be out of heating oil. That said, just because you have no heat doesn’t necessarily mean you are out of heating oil. Sometimes a burner simply needs to be reset to be restarted. In other cases, there may be air in the feed lines, or a clogged filter that needs to be replaced.

diesel is a substitute for heating oil
Diesel if a great substitute for heating oil if you are running low on or out of heating oil.

If you suspect you are out of heating oil, there are a few steps you should take:

  1. Verify that you are actually out of heating oil. Do this by checking the float gauge on the tank. Remove the plastic cover and gently lift up on the disc to see if the float is stuck. If it moves freely and the disc sinks to the bottom, you may be out of heating oil. (If you are not out of heating oil, skip to step 4).
  2. Go to the gas station and buy 5 or 10 gallons of diesel fuel. Diesel is a perfectly fine short-term substitute for home heating oil.
  3. Locate your oil tank’s fill pipe on the outside of your house, and remove the cap. Pour the diesel fuel down into the fill pipe so it can enter the tank. Do not attempt to remove a plug from the oil tank in your basement and add the fuel that way.
  4. Wait 5-10 minutes for any sediment to settle back down to the bottom of the tank. Then, press the reset button on your burner to start the system back up. If it does not start up, you may have to bleed the lines to release any air in the system. This can be a messy process, so we do not recommend this if you are not mechanically inclined. For a more detailed action plan if you are out of heating oil, check out this post here.

When You Are Low On Heating Oil

If you are getting low on heating oil, you run the risk of your system shutting down. This is because some tanks cannot use all of the oil in the bottom of the tank. There is sometimes sludge in there, but often time the feed lines come from the top of the tank and simply don’t reach all the way to the bottom.

If you are low on heating oil and cannot get a delivery right away, think about getting some diesel. Your house can use 5-10 gallons of heating oil per day in the cold months. Adding diesel once a day for a few days will certainly help you sleep better until the truck comes!

When adding diesel fuel to your heating oil tank, make sure you locate the fill pipe on the outside of the house. The fill pipe (shown on the right in this picture) will have a hex-shaped fitting on the cap. Remove this fitting and pour in your diesel fuel. The pipe on the left with a mushroom-style cap is the vent pipe. This is where air escapes the tank.

Diesel Is a Great Short-Term Substitute for Heating Oil

If you are worried about running out of heating oil, make sure you order heating oil right away! You can check prices and delivery dates on a site like FuelSnap. Once you’ve ordered heating oil, run to the gas station and buy 5 or 10 gallons of diesel. Diesel is taxed differently than heating oil, so it tends to be more expensive.

That said, the cost of frozen pipes as a result of a runout is far worse! Adding diesel every day or two until you get a fillup should help you avoid a runout. To see how many gallons your house requires on a cold winter day, check out this guide here. Alternatively, consider installing a Smart Oil Gauge. A Smart Oil Gauge will tell you exactly how many gallons per day you are using. It will even give you a countdown of days to 1/4 tank and 1/8 tank.

Happy heating,