Check the gauge and the flame. Rust means replace.

The easiest sign is your tank’s built-in gauge — if it reads below 20%, it’s time for a refill. Don’t wait until it’s completely empty; you’ll suck air into the system and make yourself bleed the lines.

Weak flame on your grill or heater is another dead giveaway. If it sputters or burns orange instead of blue, you’re low.

For replacing, look for rust, dents, or damage. Any corrosion on a tank, especially near the bottom or around the valve, is unsafe. Also check the date stamp — most tanks have a 12-year lifespan (10 years if aluminum). If it’s expired, don’t mess around. Swap it.

Refilling is cheap. Replacing a corroded or expired tank is cheaper than a leak.

Trust your nose, too. Propane is odorized. If you smell rotten eggs near the tank, you’ve got a leak. Call your supplier immediately.