I found old steel jerrycans holding ~50 gallons (~200 liters) of heating oil. They were stored in a place where temperature can go below -5°C.
Is it safe to use it for heating?
If so, should I mix one can at a time into the main tank (in order to maximize the dilution of the "bad" oil into the "good" one), or should I pour everything in my nearly-empty tank (to avoid wasting one full tank of "good" oil) ?
Should I filter this and how?
Thank you very much!