Heating oil tank (plastic tank) - how to read the fill level?

Sure, the method obviously works too. More elegant would of course be a measurement that I can read on a display without having to hang a tape measure in every time.

We had a meter installed on the heater ourselves. Since I record my consumption monthly, my Excel warns me with a nice red cell when I only have 1000 liters left in the tank.

With a normal plastic tank, the fill level is clearly visible and can be easily determined with a bit of math. You don’t need it to be accurate to the liter!

Simply mark before filling, then fill heating oil. Calculate the difference, divide liters by that, and you will know exactly how many liters correspond to one cm.

Attention: Heating oil tanks should never be emptied completely... Always order some before that!

At the moment, the heating is also completely turned off because I really cannot see how much oil is in it. My assumption is that it is completely empty. @ Deliverer: Which meter did you have installed?

Um - I don’t have a type designation on hand. But it is a mechanical meter that shows the absolutely consumed amount of oil in liters. Every HVAC installer should be able to get something like that. It looks like a typical water meter.

The thing with "X-raying" the tanks would have suited me too. But on the one hand, my tank is in a separate room only accessible by crawling through a half-door at chest height, and on the other hand, it is made of metal...