How To Read Your Home Fuel Tank Gauge

To manage your heating oil deliveries, one simple but important task you’ll need to master is reading your tank gauge. It’s pretty easy to do: if you haven’t tried it, here are the basics.

For Heating Oil Tanks:

Your heating oil tank gauge is usually a clear glass or plastic cylinder located at or near the top of the tank. The gauge is marked with numbers that look a lot like a car’s fuel gauge: F, ¾, ½, ¼. A red marker or float tells you how much fuel you have left; if the marker is at the bottom of the gauge or not visible, your tank is empty (or close to it).

To make sure the gauge is working, carefully remove the outer case and gently press the float down. If it bobs back up to the original position, the gauge is working. If the gauge is not working have the heating system repaired.

Two more things to keep in mind:

A common heating oil tank size is 275 gallons, but that’s a little misleading since a 275-gallon tank actually only holds about 240 gallons of fuel (the remaining volume is left for air and debris). That means that if your tank 275-gallon heating oil tank is half-full, you really only have about 120 gallons left.

Many factors will affect the speed at which you will use up your heating oil – the weather, the efficiency of your heating equipment, and the air tightness of your home, to name a few. But here’s a rough estimate: If outdoor temperatures average about 32° over a 24-hour period, a 2,500 square foot house will burn about 6-7 gallons of heating oil per day.

Find the fuel gauge: Your oil gauge is a clear tube with a float inside and will be located on top of the oil tank. A standard residential oil tank holds 275 gallons. Based on that size, the following readings indicate how many gallons of oil your tank contains. The float goes up and down according to how much fuel is in the tank:

F (full) = 275 gallons
3/4 = 200 gallons
1/2 = 130 gallons
1/4 = 70 gallons
1/8 = 40 gallons
E (empty) = near empty

Do NOT always trust your gauge; they can be finicky. You will need a straight stick to manually check your heating oil level in an oil tank.

Remember: We recommend ordering heating oil when your tank is one-quarter full rather than ordering in a no-heat emergency.