How to Read Your Tank Gauge
Learn how to read your tank gauge—and you’ll never wonder how much propane you have left again!
Video courtesy of the Propane Education Research Council (PERC).
Knowing how to read your tank gauge is an important skill. It can help you determine when you need to call for a fuel delivery, and it can help you avoid having to get it inspected. That’s right—if your tank runs out of propane, national safety codes require that a qualified professional test your system before you can turn it back on.
Here’s what you need to know:
When it’s in your tank, propane is stored as a liquid. However, before it leaves the tank, it changes to gas. (Ever hear of liquid petroleum gas? This is where that name comes from.)
Propane expands and contracts as temperatures rise and fall. With that in mind, we only fill tanks up to about 80% of their actual capacity. This way, the propane has room to expand when the weather is hot. (And when propane expands, it really expands: It can actually expand about 17 times more than water within a given temperature increase.)
So a tank that is on 80 is actually considered to be full, and a tank on 40 is half full. (Underground tanks can accommodate a slightly higher volume of propane as they have automatic insulation against the heat.)
If you have an outdoor propane tank that gets sunlight, be sure not to paint it a dark color, as this will absorb the heat unnecessarily.
Let us know if you’re due for a delivery!
What if the number on the gauge fluctuates?
If you see that the gas tank reading fluctuates at a moment’s notice when the temperature changes, it’s ok. And it’s important to remember that the amount of gas in the tank stays the same when this happens—only its density changes.
Whether you use propane for your fireplace, to heat your home, for your stove, for your pool or spa or another reason, the gauge on your tank tells you where you stand in terms of needing a delivery.
If you look at your tank gauge and you have questions, please contact us and we’ll be happy to help!
Would you like to learn more about what J&B Propane can do for your home or business in College Station, Madisonville, Huntsville or surrounding areas? Contact us with your questions and we’ll be happy to help!
Try this tool to get an estimate of how much fuel you need!

1. Check your tank gauge:
Look on top of the propane tank for a gauge similar to the one shown here.
The approximate amount of fuel you have will be displayed in percentages, in increments of 5%, up to 85%.
2. Select the amount of fuel you have:
This means you have approximately 0 gallons of propane in your tank.
Amount needed to fill tank: 0 gallons.
3. Order fuel:
Contact us with the number of gallons you need. You must be able to hold 150 gallons or more to avoid a delivery fee.