How do I check how much propane is left in my tank?
For a large home tank, read the float gauge under the dome lid — it shows a percentage, not gallons, and a full tank reads about 80%. For a 20 lb cylinder there's no gauge, so weigh it, clip on an external gauge, or run warm water down the side and feel for the cool line where the propane sits.
Big tanks: read the dial, remember it's a percentage
Home and cabin tanks — the 250- or 500-gallon ones — have a float gauge showing percent full under the dome lid. A 'full' fill only goes to about 80%, leaving room for the liquid to expand, so 80% is topped off, not shortchanged. Multiply the percentage by the tank's capacity for a rough gallon count: a 500-gallon tank reading 30% holds around 150 gallons. Schedule a refill before it drops too low rather than waiting for empty.
20 lb cylinders: no gauge, three tricks
Weigh it — the tare weight ('TW') is stamped on the collar; a full cylinder is the tare plus about 20 lb, so subtract to see what's left. Or clip on an inexpensive external gauge that reads the level.
Or the old warm-water trick: pour a cup of warm water down one side, then run your hand down the metal. The liquid propane inside keeps the tank cool, so you'll feel a distinct line where warm turns to cool — that's your fuel level.
For cabins and second homes
Up our mountain roads, a remote tank monitor earns its keep — it reads the level from your phone so you're not driving out to check a dial, and you'll never open the cabin to a cold, empty tank in January. We'll advise on setup alongside your propane supplier. Call (828) 545-0525.
Related questions
- At what tank percentage should I schedule a propane refill?
- Are remote propane tank monitors worth installing for a second home or cabin?
- What size propane tank do I need to run a gas fireplace?
- How long will a 500-gallon propane tank last if I use my fireplace regularly?
- Should I set up automatic propane delivery or stay on will-call if I use my fireplace a lot?
- How do I know if my house has natural gas or propane?
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