Can you reuse 1 lb propane tanks?

It wasn’t long after we first got into camping that we realized there must be a better solution for carrying propane for our Coleman stove than in the disposable one-pound cylinders. After finding out that fifty million of the steel canisters are disposed of each year by campers like us, and that a quarter-million of them simply become litter, we decided it was time for a better solution.

Thinking that we were doing the environmentally responsible thing, we bought a small brass adapter on eBay and began refilling our own 1 lb propane bottles, only to learn later that doing so makes them illegal to transport. One-time use, disposable propane cylinders aren’t designed to the same specifications as refillable ones, and thus aren’t lawfully transportable, according to the Department of Transportation. Thankfully, we never had any accidents while transporting our refilled bottles, yet if we had, we might have been liable for any damages and paid a hefty fine.

One Incident in 10 Years Was Enough

After about a decade of refilling used one-pound Coleman and Bernzomatic propane bottles, we only had one of them develop a leaking valve, after it had been re-used about ten times. About halfway down Old Monarch Pass, west of Salida, CO, we smelled propane wafting from our cooking gear box in the back of the Jeep and had to pull over to deal with a leaking 1 lb Coleman bottle. Gas wasn’t leaking from the small relief valve on the side of the cylinder (as sometimes happens with abrupt temperature changes) but rather from its main valve, which had probably began to wear out with reuse.

This incident was enough to convince us that (in addition to being illegal to transport)  refilling our used one-pound propane canisters probably wasn’t the safest alternative.

From the DOT Website:

Refilling 1 lb Propane Cylinders (For Emergency Use Only)

If a situation ever arises where you really need to re-fill a Coleman or other one-pound disposable propane cylinder (for use in a Mr. Buddy portable heater during a blackout, for example) the simple process we used does work. However, there’s even a better way than this, which we’ll get to later.

Whichever method you use, always remember that propane is a dangerous, flammable gas, so performing this process carefully and safely is very important. The photos above show some of the steps we used to refill our disposable Coleman one-pound propane bottles.

There are many videos showing how to do this and our post isn’t meant to be a tutorial on how to do so, but we’ll explain the basic principle of how it works.

How We Once Refilled Our One-Pound Disposable Propane Canisters

Disclaimer: The following is not to be used as instructions and is for illustrative purposes only.

Back when we used to refill our used Coleman propane cylinders using the old method, we’d find a clear spot outside on a cool day when there was some breeze blowing. After purging the remaining gas from our one-pound cylinder, we attached it to an inverted 20 lb. tank, and slowly opened the main valve. After about thirty minutes, we’d close the main valve, return the tank to its normal upright position and unscrew the 1 lb. canister. A better description of the whole process can be found here, on a website that sells a tank adapter similar to the one we used.

(Some people chill their 1 lb. propane canisters in a small bucket of ice water, etc. This condenses the gas and lowers the pressure so you can refill with a bit more propane. Careful not to overfill!)

To make sure we hadn’t overfilled them, we’d always perform a quick check using an old postal scale to see that our newly refilled 1 lb. propane bottles wasn’t any heavier than a new store-bought one, as well as to check for leaks before storing it away.

Downsides of This Method

• You typically can’t ever fill a 1 lb. bottle to the same level as when it was new. *
• Unless you’re using a special stand, the upturned tank is awkward and can tip over.
• Disposable 1 lb. bottles and their internal valves aren’t made to same standards as refillable ones.
• DOT-39 cylinders (disposable type like Coleman, Bernzomatic) are illegal to transport if refilled.

* There is a way do get more gas into a cylinder, but it’s more complex and requires loosening the pressure-relief valve.

Two Better Alternatives To Refilling Used 1 Pound Propane Bottles.

Option 1 – Flame King 1 lb. Refillable Cylinders

Since learning that owner-refilled disposable cylinders aren’t legal to transport, and that they’re not made to the same specifications as refillable ones are, we switched to carrying a couple of DOT approved refillable one-pound propane cylinders, made by Flame King. This simple system uses a special filling valve with a long extension, along with an optional propane tank stand, which solved the problem we once had of inverting the 20 lb. tank during the refilling process.

Option 2 – 5 lb Refillable Mini Tanks

A five pound refillable propane cylinder also works very well for fueling camping stoves, with the added benefit of lasing five times longer than 1 lb. bottles, and being refillable anywhere larger tanks are filled. The Gas Growler is one example of a five pound mini-tank that is easily stored in the back of a vehicle in it’s padded carrying case. Many in the overlanding community like to carry this size propane tank since one can last as long as a month, depending on how many meals you cook a day.

The Bottom Line: Should You Ever Refill a 1. lb Propane Cylinder?

Coleman, Bernzomatic and other brands of disposable propane cylinders don’t feature heavy-duty brass tank fittings or long-life internal valves. Disposable cylinders aren’t made with the same thickness of steel (just pick one up and you’ll feel the difference) nor do they have the DOT seal of approval for reuse which would make them legal for transport. However, when making the decision to refill a cylinder, the real reason you should avoid this practice is for your own safety and that of others, not for fear of being caught by the DOT.

Benefits of Refilling Your Disposable 1 lb Propane Bottles With a Flame King or Similar System

When it comes to saving money, using some kind of reusable, refillable propane cylinder for your Coleman stove is really a no-brainier. There are the environmental benefits as well, plus not having to deal with properly disposing of all the empty canisters at the end of the camping season. In terms of savings, it currently costs about $20 to fill a 20 lb tank,  while a 1 lb bottle costs us around $5 at Walmart. It’s easy math, and you can clearly see that refilling an approved tank can save a lot of money over the long run.

In addition to sometimes running our Coleman camping stove directly from a 20 lb. tank, using a 5′ propane adapter hose,  we’ve also been using two 16.4 ounce Flame King propane cylinders. Because these are so easy to refill, we normally don’t bring a 20 lb bottle unless we plan on being gone for more than a week.

At about $57 each for the bottles, we estimate that we’ve saved enough so far to pay for at least one of the canisters, and by the end of next season we should recoup the cost of the other, plus the cost of the $25 Flame King filling valve.

Disclaimer: We don’t advocate refilling used disposable propane bottles. This article does not constitute instruction. When using any approved system to refill a re-usable 1 lb cylinder, be sure to follow all of the manufacturer’s instructions to the letter. Full Disclosure: This post may include affiliate links to products we recommend. Our readers never pay any extra when using those links.

Sources:

https://www.phmsa.dot.gov/regulatory-compliance/phmsa-guidance/stop-never-refill-1-lb-propane-bottles-0

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