How to refill a small 1 lb propane bottle using a big standard size tank

[Kyle in Woodstock]

Thought you guys might find this useful.

If you have a small portable grill or a Performer, or heater, etc....then you probably go through many of those small green or blue propane tanks.

You need a few things
- Adapter
- Big tank with gas in it
- Small Allen wrench or screwdriver

https://www.amazon.com/exec/obidos/ASIN/B077SP5BJP/tvwb-20

That's the adapter I have but there are many options on Amazon or at your local store.

Also, make sure you wear safety glasses and leather gloves.

I worked at an Ace Hardware for 10 years and filled hundreds on big tanks and got freezer burned many times. It doesn't feel too good and takes a while to heal. When the propane leaves the tank and mixes with oxygen it gets COLD!

Anyways....

So put the adapter on to your big tank first, very important you put adapter on the big tank first since it has an Overfill Protection Device built into it....small tanks don't

Next, get the small tank and purge the air out of the tank. Do this by sticking an Allen wrench in the middle area where the gas goes in/out. Just let out the air until you hear it become faint and barely coming out.

Next, slowly flip your big tank upside down.

Then screw your small tank onto the adapter.

Next, with the big tank still upside down, slowly open the valve. You'll hear the propane flowing into the big tank.

Once you hear the propane stop flowing, close the valve on the big tank. Flip it back upright. Remove the small tank from the valve. And you are done.

 

[JKalchik]

When the propane leaves the tank and mixes with oxygen it gets COLD!

I'm going to pick a nit here.... oxygen has nothing to do with the heat loss, it has everything to do with the LP transitioning from a liquid phase in the tank to a gas phase. It's called heat of vaporization and is a very chilling effect. It's already cold if it hits atmosphere.

This is the same reason that very fine water misters work as air coolers. The very fine liquid phase droplets absorb heat from the surrounding atmosphere as they evaporate, thus giving you the cooling effect.

 

[Kyle in Woodstock]

I'm not a scientist. I just know that once the propane leaves the tank and is in the air it turns into a gas and is very cold....and have scars to prove it!

 

[JKalchik]

I'm not a scientist. I just know that once the propane leaves the tank and is in the air it turns into a gas and is very cold....and have scars to prove it!

Oh, I'm *NOT* disagreeing. I grew up with 3 1,000 gallon pigs feeding liquid LP to multiple corn driers (we could drain a pig in 18 hours, and this was a fairly small setup.) I've seen what happens when liquid LP (or liquid anhydrous ammonia) gets sprayed out, and have absolutely zero desire to have my bodily parts closely involved.

For anybody listening in..... this really is not a difficult procedure, although some government agencies would probably be pretty unhappy for you to be drawing liquid phase out of a 20 lb. bottle. If you do decide to wear gloves of any sort, the worst possible thing that could happen would be to let liquid LP run down inside the cuff right next to your skin. In a confined volume like that, when it boils off, it'll pull heat right out of you, leading to a far worse cold burn.

 

[Bruce]

I am not going to get into the freeze thing here, but I will lend my experiences having done this.

I used to do this for my Q100/Q200 grill(s) until I decided to go strictly with a hose and regulator off the big tank. I still used them for my camping grill, but then tapped into the camper tank so I don't use the small tanks at all really any longer....
That being said, when I did use them. I found the way to get them FULL is to cool down the small tank in a fridge or freezer for a couple hours. Then put the adapter in the 20lb tank, turn it upside down and then attach the small tank to the adapter. Then open the big tank and let it flow. Most instructions say to let it go for a minute or two after you no longer hear the gas flowing. If you do that, you will only get about a half a tank. Leave it hooked up and going for a couple hours longer and it will fill completely up like it should be.