How long does propane last?
Propane does not degrade, so it lasts indefinitely; the limit is the cylinder, which in the US must be requalified 12 years after its manufacture date before it can be refilled.
| Propane | |
|---|---|
| Unopened | Indefinitely (the fuel itself) |
| Connected | Indefinitely; check hoses and fittings for leaks with soapy water |
| Ideal storage | Outdoors, upright, in shade; never store cylinders indoors or in a garage. |
Storage tips
- Check the date stamped on the collar of 20 lb cylinders.
- Only use heaters rated indoor-safe inside, with a carbon monoxide alarm.
Signs it has gone bad
- Batteries: white crusty residue, swelling or leakage at the terminals
- Bleach: a weak smell; it may no longer be strong enough to disinfect water
- Fuel: darker color, a sour or varnish-like smell, or separation into layers
- Canisters and cylinders: rust, dents, damaged valves or a gas smell