Why Does My Oil Tank Whistle?

Date: November 30, 2018

Heating oil tank

In our last blog, we explained the various sounds you may hear from your warm-air furnace. As with any piece of equipment, many of the sounds you will hear are perfectly normal.

Now, we would like to carry over that theme by discussing another perfectly normal sound you will hear. This time, the noise revolves around your aboveground oil tank.

On a cold day in South Carolina, it can warm your heart to see an oil delivery truck pull up to your property. You know that before long, you will have a tank full of oil and one less thing to worry about–even if the wind begins to howl and snow starts to fall.

But here’s one thing you should know if your oil tank is located aboveground (or in a basement, when that option is available). As the oil driver begins putting oil in the tank, you will hear a whistling sound. But don’t worry, as we noted up top, this is normal.

Understanding the vent alarm

Besides your tank, your heating oil storage system includes the fill pipe, vent pipe and vent alarm. After our driver arrives, he connects the hose from his oil truck to the fill pipe and starts releasing the oil. As oil flows into the tank, air is pushed back out. As the air goes through the vent alarm–located between your tank and vent pipe–it makes a whistling sound. When the whistling stops, the tank is just about full.

The vent alarm prevents overfilling and the possibility of a spill. Safety codes do not allow your oilheat company to deliver your fuel if the vent alarm is not working.

Speaking of safety codes, here are a few more things you should know about your oil piping:

  • The vent pipe should be at least 1.25 inches in diameter. A narrow diameter allows excessive pressure to build up inside the tank during filling, which can cause a tank rupture.
  • PVC piping does not meet NFPA safety codes and must be replaced because they are more likely to crack when tanks are being filled.
  • It is the homeowner’s responsibility to properly maintain fuel tanks and all associated piping.

If you have any questions about your oil storage system, please contact your local oilheat company and they will be happy to help answer your questions.