The P. Gagnon & Son Blog

What’s The Shelf Life of Heating Oil?

Find out if heating oil will “go bad” if you fill your tank now

heating oil delivery maineWith winter in the rearview mirror, you’re likely not thinking about your heating oil tank or the heating oil in it.

One common question we get asked is this time of year is, “How long does heating oil last before it goes bad?”

You won’t have to worry about the heating oil in your tank “going bad” between now and when you use it this winter. Heating oil has an 18- to 24-month shelf life. Thanks to the high-quality premium fuel we deliver, treated with the fuel preservative UltraGuard, your heating oil could last even longer than that!

So, if your tank still contains some heating oil from this past winter, it will still be perfectly safe to use when you turn on your heating system next winter.

There are, however, a few reasons why it’s a good idea to fill your tank now. Let’s go through them.

Condensation: The enemy of your heating oil tank

When your heating oil tank is not full, condensation appears on the inner bare walls of the vessel. When temperatures are hotter, such as in the spring and summer, this condensation develops faster.

Condensation is a major problem for your oil tank in several ways. Bacteria growth is encouraged by condensation in your heating oil, as it creates an ideal breeding ground for bacteria. If that keeps going, your heating oil develops sludge. Heating oil sludge clogs your fuel lines, lowers the efficiency of your heating system, and, if the pipes are completely blocked, your furnace or boiler will not get fuel and your heating system will fail. You’ll be left in the cold with a big repair bill.

When condensation builds up inside the heating oil tank, it falls the inside tank wall. Because it is heavier than heating oil, condensation falls to the bottom of the tank. Once there, the bacteria it helps to grow ends up developing sediment. Sediment causes the corrosion of your heating oil tank from the inside out.
If your heating oil tank corrodes and fails, you will have to replace it as well as remove it, and clean up any leaked fuel to regulatory standards. This might set you back some serious money!

Protect your tank by keeping it full

Condensation will not form in your tank if it is kept full during the summer.

Another advantage is that you’ll have a full tank of heating oil when the heating season resumes. If a chilly snap strikes early in the season, as it frequently does in the Seacoast Region, you’ll have plenty of heating oil on hand to keep your house warm and you won’t have to worry about the difficulty and expense of emergency heating oil delivery. 
If you want peace of mind about your heating oil tank, contact us today to learn more about our TankSure® program.