I will teach you how to legally and safely refill 1 lb propane bottles for the best savings available. If you don’t already know: Coleman 1 lb propane bottles are extremely expensive (Later I will explain why it is dangerous and illegal to refill disposable propane cylinders with a refill kit). You will end up paying around $13.99 for a 4-pack at a big box store or up to $6.99 for a single 1lb cylinder at a convenience store.
Costs of Refilling Your Propane
Compare that to refilling a 5-gallon cylinder. You can get propane by the gallon (not by the pound) for $2.59-$3.50. You get about 8.35 pounds PER gallon. Let’s assume you purchased the Coleman 4-pack which comes to a price of $15.00 after tax (7.25% in CA) and is, therefore, $3.75 per pound. If you get your fuel from a filling station, you only pay $0.332 per pound. You can already see the savings without doing the math.
You will need a refillable 20 lb tank propane tank and the Flame King refill kit $45-$50, which you can find online at FlameKing.com or Sportsmans Warehouse. The kit comes complete with a stand, adapter and a 1lb tank. You can purchase more tanks for about $15.00 each.
Have your own way to mount your tank? You can purchase the adapter here for about $23.00. If you don’t already own a 20 lb tank, you can find one at your local hardware store. I purchased mine at Tractor Supply for about $35.00 (yes, these are some upfront costs, but look at the long-term savings). You can check 20lb tank prices online here. I recommend getting a digital scale for precise measurements but this is optional. I use an AWS digital scale which I purchased on Amazon for around $12.
Once you have all of your equipment, you’re ready to start filling!
How To Refill a 1lb Propane Tank
Place your 20 lb tank upside down on the stand, hook up the adapter and attach your refillable 1 lb propane canister. Use the provided hex key wrench to open the bleed valve on the 1lb tank. Press the valve lever on the adapter and let the process begin. You will start to hear liquid propane enter into the cylinder. The large tank needs to be upside down because you want the liquid propane to fill the small cylinder, not propane in its gaseous state. Otherwise, you’ll only get a fraction of the fuel!
The stand allows you to hold your 20lb tank upside down and hook up the 1lb tank below it without touching the ground. The filling process is pressure equalization in both tanks. Once you see the propane gas start shooting out of the bleeder hole, you know you’re done. This took me a better part of 1 minute to fill.
If you purchased the optional digital scale then you can make precise measurements.
I start by weighing the empty cylinder (make sure your weight setting is in the “oz” mode), press the ‘tear’ button and this will zero the measurement. Then fill the cylinder, place it on the scale, and repeat the process until you reach 16oz (1 pound). You can also weigh the cylinder without tearing the empty weight, write down the weight and add 16oz to the total weight. Once it’s full, you can write down the weight on the cylinder for future use.
That’s it! You’re done and ready to enjoy the savings by never having to purchase another disposable propane tank again! Additionally, you can take a little pride that you’re not dumping precious resources into landfills.
Here is a detailed version of how I did it and the equipment I used.
The stand is designed to support the 20-pound bottle but not to leave it on the stand if you’re not using it. There is no support feature from accidentally knocking the bottle off the stand. It is easy to assemble with a pad, 2 U-shaped support bars, wing nuts, screws, and washers. You don’t need any equipment except your hands to assemble.
The attached propane refill tap station ready-to-use.
The refillable 1 lb tanks each come with a hex key as well as a plastic tank valve cap. I purchased 3 additional one-pound tanks and each came with a hex key.
The propane cylinder cap is threaded and has four rings to easily carry with your fingers or for whatever you wish to use them for. My only complaint is that I was it was a little more sturdy, but they’re a lot better than the disposable caps.
The relief valve is shown just above the main valve.
Pictured is the propane bottle and refill adapter together. You will notice there is a U-shaped protrusion that will fit into the tank valve. This is to prevent the filling of propane cylinders not approved by Flame King (or the Department of Transportation).
The complete set-up with both propane bottles is ready to go. I like how the 1 lb propane tank sits off the ground for easy attachment. The relief valve is easy to access should your propane refill begin to overflow.
Here is where the hex key attaches to the relief valve. Flame King suggests opening the relief valve slightly to allow liquid propane to occupy the space inside the 1 lb propane cylinder.
Once you have everything securely attached, you are ready to operate your refill station. Begin by opening the main valve on your 20 lb propane tank.
Press and hold down on the lever to begin the propane refill process. I personally like how you can start and stop the process by just letting go. As you press down, you will hear the liquid propane start to flow into the smaller propane tank. While you’re filling the propane tank, open the relief valve just a hair. You will hear and smell escaping gas.
This is ok because it’s just the oxygen and gas coming out. The liquid propane is filling from the bottom up and pushing out the oxygen. Once you begin to see a white mist of propane, close the valve on your 1 lb propane cylinder and depress the valve on the propane refill adapter.
That is it! According to Flame King, you have filled the tank to approximately 80% (around 1 lb of fuel).
Once you are finished, it is now time to detach your 1 pound propane cylinder from the tap. This is where gloves will come in handy. First, close the main valve to your 20 lb cylinder.
When removing the 1 lb content from the propane refill station, there is a high chance propane will vent out from the tap. This is extremely cold and could cause a burn to some degree (no pun intended). There is also residual in the tap system and that can spray out cold fuel.
I found that as long as the main valve is closed, you can press the fill lever and release the pressure from the tap. Remove the refill kit from the 20 lb tank and finally take the main propane tank off and flip right side up. Store all your propane tanks in a well-ventilated area. Do not store where any escaping fumes could be collected next to an ignition source (water heater, gas dryer, etc).
As an added measure of safety, I spray soapy water on the end of the 1lb propane tank. If you see small bubbles forming, then you have a leak. Try depressing the main valve and let it snap shut. This usually does the trick. If nothing, then wipe off and you’re ready to store or use. Cheers!
Dangers of Refilling Disposable Propane Cylinders
Now I explain why it is dangerous and illegal to refill those disposable cylinders. Disposable 1 lb propane tanks are convenient for their intended applications and looks like an easy job. Unfortunately, they are not supposed to be refilled and according to federal law, it is illegal to transport refilled disposable cylinders. Getting caught and having it proven that you refilled the tanks seems very unlikely, but it’s still not worth the risk.
Technically, you can refill them so long as you do not transport them and keep them on-site. The valve design has an overflow safety feature that is supposed to release propane if the pressure is too great. I have refilled several containers with a standard refill adapter (which some believe is a great accessory to their camping gear) with no issue and many other people have done this too.
Chances of a critical failure may be low, but I ask you this question: How much is your life, your loved one’s life, or your body worth to you? Is it worth the risk to save a few dollars to refill disposable tanks? I’m one to spend a few extra dollars for better quality material and peace of mind.
Weight Difference Between Propane Tanks
The disposable Coleman DOT 39 propane tanks are much lighter than the Flame King tanks. The disposable tanks have an empty weight of 13.37oz while Flame King is 22.46 oz. A difference of 9.09 oz or over a half pound! That is more metal on the cylinder. Simply holding both empty tanks in hand, you can easily feel the difference in weight.
By comparing both cylinders, one can see the difference in the welding between the 1lb propane tanks. The flame king simply looks more durable while the disposable Coleman propane cylinder is seam welded.
The reason is metal fatigue (learn more about metal fatigue here). Every time you deplete the propane out of the Coleman bottle, the pressure naturally decreases. Refilling the tank quickly introduces pressure back into it. Even with the pressure relief valve, repeating this process a lot of times begins to wear on the structural integrity of the cylinder and it can increase the likelihood of a catastrophic failure. This is especially true around the seam weld.
If you reload ammunition, you know that you can only reload the brass x-amount of times before you have to retire it. Refillable tanks are DESIGNED to be depleted and refilled over many uses, and they’re DOT approved for transport.
If you are dead set on refilling disposable 1 lb propane tanks, customers can purchase a refill kit on Amazon for a price of around $6. Those things are a pretty cheap accessory to your camping gear. I found a high-quality brass adapter at Harbor Freight for $20.00.
Even with that, you need to find a way to support the 20lb tank upside down. Then, you will need to repeat the process of attaching the 1lb propane tank to the adapter, open the valve, fill until you hear the propane stop, bleed the Schrader valve (which reportedly tends to leak after repeated bleeding) or unscrew it, re-attach and repeat until it is full. With the
Flame King, you get the stand, fill valve adapter, and a hex key which allows you to fill a tank in about 1 minute. If you value your time, this is another way to save money.
