569 of 576 people found the following review helpful
on April 8, 2010
EDIT: see comment at end regarding a simple means to completely fill the tank.
I don't generally criticize other reviewers, but I think some of the reviewers here (one and two stars) have gotten this confused with a different product. This device will not "freeze up" your grill, as it does not attach to your grill; and there is no "shut off" valve necessary, because your 20-lb tank already has a shutoff valve. I suspect those reviews are for an adapter to attach a 1-lb tank to an appliance that normally takes a larger tank (which I also have, looks somewhat similar to this, and costs about the same).
A really important safety consideration: tighten the adapter to the big tank with a wrench. When you are removing the 1-lb tank after filling, you want the little tank to detach from the adapter (so the little tank's valve closes) and not come off with the adapter still on it, in which case the propane inside the little tank is going to blast out. Wrench-tighten the adapter to the big tank, hand-tighten the little tank to the adapter.
Rather than repeat other reviews of this simple (and quite overpriced for what it is, although it will indeed pay for itself) device, I'll just give a few hints from experience. The sequence of what tank gets connected first is quite important, but not so much for safety as for operation. You will need to put your 1-pounder in the freezer; physics students will note that the 50 or 60 degree F. drop in temperature will create barely enough pressure differential to even start transferring propane form one tank to another, but the secret is that pressurized propane is a liquid so just a little vacuum gets a disproportionately large transfer. But as I discovered...attach the Mr. Heater to the big tank FIRST because if you attach it to the 1-lb bottle as you take it out of the freezer you'll hear a WHOSH! as air rushes in to fill the vacuum, and you're not gonna get any propane transferred after that! (Cure: leave with Mr. Heater now attached on counter for several hours while the air inside warms back up, remove Mr. Heater, back to freezer, avoid stupid mistake next time.)
With the outside temperature around 70 F., I can only manage about 1/3 full. Frankly, submerging tanks in hot and freezing salt water is too much effort for me and I suspect for most people too, and I'll bet most people don't have a vacuum line to draw a vacuum first. In theory, if you pulled a vacuum on the 1-lb tank you'd wind up filling completely full and that would be downright dangerous, but as a practical matter the propane flashes off as it fills and eliminates the vacuum before it's completely full - I've seen people warning never to fill a tank 100% of the way full but actually it's impossible to do unless they override the tank's pressure relief valve (bad). But if getting 2/3-3/4 full takes an ice cream salt bath and a double boiler and a vacuum pump while getting 1/3-1/2 full takes a brief pop in the freezer, I'll settle for refilling a little more often.
You'll also hear people say it is illegal to refill or transport refilled tanks. That's not true, at least on a federal level, where the restriction is on commercial transport for sale or use in support of commerce (and even then, what's illegal is actually the mis-labeling of the tank, not the refilling - 49 USC 5124 cites 49 USC 5104, which deals with hazardous tank labels). But that doesn't mean your state agrees, so there could be state or municipal contraints on transport.
EDIT: I discovered an incredibly easy way to fill the tank, with no salt ice, hot water, or magic. READ THIS COMPLETELY BEFORE YOU TRY. Do the cannister-in-the freezer thing and fill it the expected one-third or so up. Don't put the big tank in any hot water; don't put the little tank in ice water or an ice cream bucket; don't stick needles in a Troll doll. Just put the little tank back into the freezer for a few more hours. Now, repeat the filling and you can refill the small tank as full as you want! Which brings me to an important safety disclaimer: while I know from physics it is impossible to truly fill the tank 100.000% because of the evaporated gas inside, by letting the second fill continue until all transfer finished (no more hissing sound), the 1-lb tank was so full that I could not even hear any liquid slooshing inside when shaking the tank. That's probably DANGEROUSLY full, and I connected it immediately to my BBQ to run some of the propane back out of it. So either do this carefully or don't do it at all, and remove the tank BEFORE the transfer is completed (in my experiement with a sample size of one, I could hear the transfer clearly slowing down before the hissing completely stopped).
475 of 481 people found the following review helpful
on January 27, 2008
For safety concerns just use the source tank valve for on/off control...To fill each 1 lb. bottle more completely simply put those containers in a refrigerator or even a freezer for a few minutes AND put the 20/40 lb. FULL tank in hot water and/or in the Sun...The key here is to maximize the pressure in the source tank and minimize it in the receiving 1 lb. bottle allowing for more propane to transfer before the pressure equalizes...I've been filling these little bottles for years using this type coupler and while they may not get 100% filled as when new they can reach 80-90% with regularity when the above steps are taken...Keep in mind NO Propane tank is completely filled anyway or at least it shouldn't be to allow for excessive heat expansion when full..
Even if trying to refill in a freezing or below environment simply heating the 20/40 lb. bottle up by leaving it in a heated indoors for a few hours and/or in hot water will help tremendously to get more transferred...
When you get tanks refilled commercially the source has pump assisted pressure so this always allows for a complete fill...
468 of 484 people found the following review helpful
on September 27, 2009
I have had this or a similar product for several years now. I live in the mountains, and go camping a lot, and sometimes set up camps and leave, going to work, backpacking, etc, and dont return until night or even a few days. I had two small bulk containers, one for a propane lantern, and one for a little heater and both were stolen out of my closed tent. Since the small refillable propane tanks (small bulk tanks cost more than the regular 5 gallon bulk tank) are expensive, I switched back to the 16 oz type disposable type. I have messed with all different ways of refilling these babies, and here are my suggestions and results.
1. If you only camp once a year (or twice), just spend the $3 each on a couple new 16 oz disposables and be done with it. If you set up "big hunting type camps" you are probably going to have a big bulk tank or 2 anyway, with a propane tree on it or some similar setup for lanters, cooking, etc. or more than likely, have a trailer, and you probably don't need advice from me anyway.
2. Though you can get a complete (and even a little over) fill by pulling the little "bicycle valve" overflow protection valve while filling, these tanks are not really ment for that, and frequently enough (one out of 4 tanks maybe, my experience ... maybe one out of every 6) this valve, once pulled out, will leak, and the tank and refill will be useless. Even though the tanks are filled all the way, I do not recommend this due to the higher percentage of leakers.
3. I recommend following the instructions, which requires putting the bulk 5 gal. tank in the sun for a few hours (let it get nice and warm), and the little 16 oz tanks in the freezer, using temperature differential as a pump. Then, grab one tank from the freezer and attach to the refill device/bulk tank, make sure everything is decently tight, and open the valve on the bulk tank (which is upside down - I usually do it on the tailgate of my Toyota Tacoma). You can hear the propane going into the small tank, and when it seems like its not going to get any fuller - usually around 45 seconds to a minute, shut of the big tank valve and unscrew the little one, and go and get another nice cold one from the freezer (little propane tank, not beer). When I first started refilling them, I weighed them to see how much propane I got in the little tank. When I was a newbee, and didn't know what I was doing, and didn't have enought temperature difference, I wouldn't get hardly any liquid propane in. Then I learned the "pull out the bicycle valve trick" and found I could fill them even a little more full than new, by weight on a postal scale. Now and finally, I just put the big tank in the sun, and the little ones in the freezer, and I don't weigh them anymore, but my "picking them up" scale tells me that they are probably somewhere about 1/2 full, or a little more. This is enough for me, for just one single mantle lantern and one propane stove. Usually they don't leak if you don't mess with the overpressure protection valve.
Lastly, a couple things to keep in mind (principles of propane refill) - propane is always at a constant pressure, at a certain temperature. As some of the gas escapes, or is burned, the pressure that would drop is refilled by propane gas which has expaned from some of the liquid. Therefore, if both tanks were equal in temperature, and you hooked one to the other and opened the valve, (assuming the big tank is upside down so the liquid proane is comming out and not gas - if you refill with just gas, you might get 30 seconds worth of gas into the little tank, which is basically nothing and not what you are looking for) the smaller one would only get maybe 5% or 10% full, untill both tanks were under the same pressure. The object is to get as much "liquid" propane in. The more temperature differential, the more liquid you will get in, because the pressure will be lower in the cold tank. Of course, the bicycle valve trick works great (wear gloves on your right hand, because the propane gas is cold when it comes out/evaporates, and no smoking). But, because they weren't made for that, seem to have a hard time seating themselves again, even when pushed in, etc. Now that I've been refilling these little babies for a few years, it seems so quick and easy, and probably saves a few bucks, and is better for the environment not throwing away a decent little tank.
So, summary - yes these work fine, but anticipate only about 1/2 full (or slightly more) small tanks.
Oh, and lastly about the no smoking comment - I stand by that, but propane gas is heavier than air (which is why you can't use propane appliances in your basement) and goes down when leaking. I've had a little leaking tank within 2' maybe of a flame which was higher and screened, and it didn't catch, but I was watching it closely, and threw the tank away shortly thereafter. Try that with gasoline fumes, and you will find yourself in a big explosion of flames!
Sorry for the long review, hopefully it will be kinda helpful.
114 of 117 people found the following review helpful
on June 16, 2011
This device works well to fill the small cylinder from the big tank but there are many things to keep in mind for best results. Here are the steps that worked for me:
1. Screw the adapter onto the big tank. The threads are backwards so you have to screw it in the direction that would normally loosen it. Set the big tank in the sun.
2. Put the small cylinder in the freezer.
3. Go work in the garden for a while.
4. Take the small cylinder out of the freezer and screw it to the adapter. Since the threads for this step are normal, you have to hold the adapter with a pliers to keep from loosening it from the big cylinder.
5. Turn the whole apparatus upside down. This is so that liquid propane goes into the small tank instead of gas.
6. Open the valve on the big tank.
7. Put on a pair of gloves.
8. When the hissing stops, CLOSE THE VALVE ON THE BIG TANK and remove the small cylinder. The gloves are to keep from freezing your hands in case you forget this step and they get hit with liquid propane. In this case, close the valve on the big tank as soon as you realize your mistake.
9. Get a nail.
10. If the small cylinder is leaking, use the nail to jiggle the valve to try to get it to stop leaking. In any case, screw the torch tip onto the cylinder to prevent loss of propane if the cylinder leaks.
11. Remove the adapter from the big tank.
25 of 25 people found the following review helpful
on November 10, 2012
This product works excellent. I've done three refills so far and I'm averaging .88 lbs of propane or 88% each refill. Here is how I use it.
Follow directions for attaching refill adapter to bulk tank.
1.) Put empty 1-pound propane bottle in kitchen freezer for about 20 minutes.
2.) Remove 1-pound bottle from freezer, go outside, and attach it to the adapter.
3.) Invert bulk tank and open the valve.
4.) Wait 60-80 seconds and close bulk tank valve.
5.) Right-side up bulk tank.
6.) Disconnect 1-pound bottle while 1-pound bottle is in the right side up position.
7.) Inspect 1-pound bottle for leaks.
7.) Weigh 1-pound bottle to measure how much propane was transferred.
8.) Leave the 1-pound bottle outside for about 15 minutes and then return and check for leaks or weigh bottle again.
From the Worthington factory my factory filled 1-pound bottles weigh 1.95 lbs exactly.
When empty, the bottle weighs 0.95 lbs. This means that from the factory there is exactly 1 lb. of propane in each bottle. I've done three refills so far and I'm averaging .88 lbs of propane or 88% full each time. I'm very happy with the adapter. Take care not to damage the rubber O-ring and it should last a long time.
30 of 31 people found the following review helpful
on November 11, 2010
I have had a Mr. Heater Big Buddy heater for almost a year now, which I have reviewed on this site. I also have one of these adapters. I burned many 20 pound tanks of propane last year, via less than a dozen 1 pound bottles refilled using this adapter. I haven't blown myself up or burned my house down. But then, I don't take crazy stupid chances either. Any propane tank, whether 1 pound, 20 pound, 100 pound, or 500 pound, should NEVER BE FILLED BEYOND 80% of capacity. My propane dealer does not fill my 500 pound tank beyond 400 gallons. This is for safety sake. That said, I cringe when I read reviews where people try to get the 1 pound bottles completely full. One reviewer stated that they had filled one to 103% of capacity. YIKES! DANGEROUS! A sandwich bread bag filled with propane makes a good sized fireball when lit off. You don't want one of those bottles venting because of overfilling when attached to a heater or near an ignition source. I do not mess with the overfill relief valve when filling. I freeze the bottles, allow the tank to warm to ambient temperature, attach adapter snugly with wrench, connect and leave bottle connected to adapter for only about a minute. I may not get a "new" fill, but I get close. I save money and stay safe. Good enough, that's all I'm after. Oh, and also, both bottles and tank are stored safely outdoors, NEVER INDOORS, so that leakers can dissipate safely without blowing up my house and killing me in the process. If a bottle is leaking, you can hear the hiss of escaping gas when held to your ear. Sometimes I have had bottles leak around the valve after refilling, because the valve doesn't seat properly. Every time, opening and closing the valve quickly several times with a nail and/or jiggling the valve stem side to side a bit has seated the valve and stopped the leak. Propane, or anything else, that flammable and under that much pressure will kill you if you don't respect it. If this adapter is used sensibly and according to instructions, there is very little chance of an accident. It costs me $10 to get my 20 pound tanks refilled, and 1 pound refilled bottles cost me 50 to 75 cents per, compared to about $3 each new, so the cost of refilling is a small fraction of new and there is no waste to speak of, so from where I sit, using this adapter is a win-win.
17 of 18 people found the following review helpful
on January 17, 2014
I'm writing this review because I had a mishap when using it that I hope I can prevent others from having. I partly attribute the problem to the manufacturer not affixing the center stem properly. I followed the directions closely as well as some good safety precautions mentioned by reviewers here (wear gloves to protect hands in-case of freezing propane leaking, have an appropriate sized nail to poke in the small tank's pin valve in-case it gets stuck). Whatever you do, make sure you do this OUTSIDE because this can happen:
After refilling and closing the valve on the 20lb. tank and then flipping it right-side up, I slowly unscrewed the small tank but the center brass pin on the refill adapter also unscrewed, staying in the small tank and keeping the pin valve open. Needless to say, propane was escaping the 1lb tank very quickly at sub-freezing temps and I dare not attempt to pull it out with pliers at that point. This very dangerous situation could have been avoided if the manufacturer had put thread-locking compound on the stem or brazed it to the main body of the adapter.
To prevent this problem:
-carefully remove brass stem with wrench or pliers
-polish the brass stem with a Brillo pad or fine steel wool
-put thread lock compound on the stem's threads and screw back into the adapter
-use a cotton swab to lightly coat the brass stem with mineral oil
-use a cotton swab to lightly coat the rubber o-ring on the inside of the 1lb tank with mineral oil before the refilling process
This adapter can save you some money, if your careful.
17 of 18 people found the following review helpful
on June 9, 2009
We had been spending lots of money buying the small propane canisters for the portable heaters and stoves. We needed a better solution and the Mac Coupler Adapter was the answer for us. We have used it many times and works great. We're saving money and find using the coupler very easy. The trick is to follow the instructions and make sure the small canisters are very cold. It works so well I bought one for my father-in-law, who thinks it works like a champ!
31 of 36 people found the following review helpful
on November 12, 2007
Useful Emergency Item to Have
This is one element of my emergency preparations here in Ohio.
My camping/emergency cooking burner, propane lantern and Buddy heater unit all work on the small canisters. This would allow me to make use of the propane in my two 20lb tanks in an emergency by letting me refill those small canisters.
30 of 35 people found the following review helpful
on September 2, 2009
With propane you need to get the source tank pressure high and get the receiving bottle to a lower pressure then the source. I start by placing the source tank in the sun. Some directions say to put the bottle in the freezer for approximately + or - 20 minutes. I would start out that way to get the bottle cold, but to keep it cold is the key. Get a small container just big enough to submerge the majority of the bottle in ICE WATER. Fill the container just enough to submerge the majority of the bottle with the ice water, but more ice then water. You need just enough water to make a good contact surface to conduct the cold. You will add either ordinary table salt or rock salt. This will bring the water to below freezing temperatures, about 15 degrees F. This will keep the bottle cold enough to almost fill, if not completely filled, depending on how warm the source bottle is. I would try not to submerge the top of the bottle as salt water is corrosive and the top is the only part thats usually not painted, so it will foul the valve and threads. For information purposes only.