Refilling small propane cylinders

I think you might be incorrect on that one. I've had a HF adaptor for years now, and invert the larger tank when refilling the smaller ones.

IIRC the overfill protection valve is a float which rises to shut off the flow passage when the tank is overfilled with liquid while standing upright. When you invert the tank as when using the HF adaptor to refill a small tank the float rises towards the bottom of the tank, which leaves the valve passage open, if there's a decent amount of liquid in the larger tank.

Course I could be wrong about that, maybe the latest valves have a secondary mechanism to close off the valve passage when the tank is inverted?

One thing I always wondered about was overfilling a smaller tank so that it might vent (or G-d forbid burst?) if the surrounding temperature rose. I'm chicken about that kind of thing so I weighed a couple of just purchased tanks on the kitchen scale, wrote the weights on them and check them after refilling to make sure they're not above their marked weights.

Agreement/disagreement or clarification of any ofwhat I just wrote would be welcomed.

Jeff

Reply to
Jeff Wisnia
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I have one also. Build a wooden stand to suport the "B-B-Q" tank upside down such that the one being refiled is setting on the table. Second cool the "refillee" (empty one) in the freezer and warm the "refiller" (full one). Works fairly well. ...lew...

Reply to
Lew Hartswick

David Seidel covers how to do it pretty well. I will just add a little to what he says. I never warm the big tank, but would if it was below say 60 degrees F. I don't vent the little tank by pulling on the pressure relief valve. If you do that, you may get some ice or something prevents it from closing completely. Not a big hazard, but a slow leak. I have always gotten it to seal again after some playing around with it, but decided it was easier not to mess with it.

I put the little tank in the freezer before filling it. If it is completely empty, it warms up rapidly when the new propane goes in. So you don't get much propane into the little tank. So chill it again and you will get a lot more the second time. Do it one more time and you are likely to get it completely full and have some coming out of the pressure relief valve when it warms up. Which reminds me, I need to refill the little tank I use for starting the wood stove before it gets completely empty.

Dan

Reply to
dcaster

I agree. I've been refilling the little tanks for about 20 years, tho not the same ones.;-) The small tank does not have to be colder than the big one if you vent gas off the little one as you fill, but it would probably help. The venting is gaseous untill the little tank is full. When filled, the venting becomes liquid and it's easy to tell if your not wearing gloves! The

20# tank is kept upside down, the little tank upright. After a few refillings the vent valves sometimes seep gas. I store these outside and use them immediatley if I can. Sometimes they will stop leaking if you fiddle with the valve, sometimes you lose the gas. I havent tried filling with the OPD tanks yet. I tried getting a non-OPD tank refilled at Amerigas by putting a sign on it that said 'FOR INDUSTRIAL USE ONLY' but they wouldn't do it. Company policy, no 20# refills on old tanks. I'm going to try the little tank in the freezer trick next. The percentage of propane lost to venting, now that the cost of propane is higher, is enough that the gas lost may be significant. Good luck and please don't smoke while refilling.
Reply to
Tom Wait

"Lew Hartswick" wrote >

Are you filling with an OPD tank? Will it empty of liquid when it is inverted? Tom

Reply to
Tom Wait

Well, I had to go and see if my memory was playing tricks on me so I tried topping off of a partially empty Bernzomatic bottle from an inverted 20 lb OPD valved tank. (A "Blue Rhino" I'd swapped out my last non OPD tank for a couple of years ago.)

Even though the 20 pounder was been sitting outside in about 35F Taxachusetts temperature, I brought it into the garage and after putting the small tank in the kitchen freezer for 15 minutes I was able to squirt a half pound of gas into it in roughly 15 seconds.

YMMV,

Jeff

Reply to
Jeff Wisnia

Tell me more about chopping a standard bottle down. I could use a smaller refillable propane bottle, preferably smaller diameter too.

Reply to
Nick Hull

Well, I removed the shrader valve and filled the bottle with water to make sure it was purged of all gas. Then I put it on the trusty old Jet 4" bandsaw and cut about half inch above the base ring and again about 4" below the base of the valve. You can't cut to close or you will hit the relief valve fixture. I covered the top in heat dam clay so I would not melt any rubber in the main valve. Then I set the MIG on the lowest setting and tacked the top and bottom together followed by a full bead all the way around. After that I filled it with water again and pressure tested it to

250 PSI with the rig I used to test my boilers. Drained the water and left it in a warm place to let it dry out before I reinstalled the shrader valve.

Made 3 of them and they are still going strong though I did recently replace a small O-ring in the top after many uses which was the dickens to get out.

Reply to
Glenn Ashmore

As posted recently, I have, and use two of these. Gerry :-)} London, Canada

Reply to
Gerald Miller

On Sun, 8 Jan 2006 09:43:27 -0600, with neither quill nor qualm, "David Seidel" quickly quoth:

Thanks, David. I'll grab one of those adapters the next time I hit the HF store. I keep some of the one pounders around for the times the power is out and I want a nice, hot cup of coffee or lunch/dinner. The 1-burner stoves are extremely handy in that case and are portable should the "civilized" world end abruptly. I also keep one for the propane torch.

-- "Not always right, but never uncertain." --Heinlein -=-=-

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Reply to
Larry Jaques

On Sun, 08 Jan 2006 12:34:46 -0500, with neither quill nor qualm, Jeff Wisnia quickly quoth:

As I just told David, I sit corrected. (Too lazy to stand)

They're protected with the overpressure valve. And don't vent them anywhere near any equipment which could self-activate (compressor, light switch, etc.) and cause a spark. (The usual common sense stuff we all know and usually do. We're -not- Darwin candidates.)

I think it should probably be said that if the tank and valve are steel, the pliers used to vent it should be protected with tape (or be made of a non-ferrous material) to avoid a spark during venting.

-- "Not always right, but never uncertain." --Heinlein -=-=-

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Reply to
Larry Jaques

My adapter is just 2 fittings soldered together. The fittings were in my junk box, but I see them at the dump all the time. The only complication was that the small tank fitting had a check valve that I had to drill out. Bob

Reply to
Bob Engelhardt
30 gallons are the smallest commercial bottles that are not required to the OPD.

If you upturn a OPD - it turns off. Cannot dump liquid from a OPD into an old tank.

When you buy a new tank - be sure the tank is dumped by the propane company. The internal gas won't burn and it just fills it. They have a special tool that allows dumping.

Martin Martin Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH & Endowment Member NRA Second Amendment Task Force Charter Founder

J> We have probably 6 of the old style 20 pounders. As a commercial entity,

Reply to
Martin H. Eastburn

The tanks auto dump and re-seal. I've had them do that in my truck on the way home. - On a cold wet day it is obvious. Tanks should not explode - Never heard of one - unless in a fire.

Martin Martin Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH & Endowment Member NRA Second Amendment Task Force Charter Founder

Jeff Wisnia wrote:

Reply to
Martin H. Eastburn

The last time I did it was with a old style tank. The next time I will have to use the OPD one now on the grill. Come summer. :-) ...lew...

Reply to
Lew Hartswick

Jeffry Wisnia's message reminded me that I ought to refill the little torch tank I use for lighting the wood stove. I like to refill before the tank is completely empty because a completely empty tank chilled in the freezer compartment warms up rapidly when you fill it. So you don't get much in the tank the first time you chill and fill when the tank is completely empty. The second time works well.

I did refill it using a 20 lb tank with a OPD valve. Worked a bit too well, filled it completely. So I had to use it to ginger up the woodstove so it was no longer completely full.

Dan

Reply to
dcaster

So how do you get gas out of the OPD into the other tank ?

Are you holding it at an angle ?

Martin Martin Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH & Endowment Member NRA Second Amendment Task Force Charter Founder

snipped-for-privacy@krl.org wrote:

Reply to
Martin H. Eastburn

I just held the 20 # tank upsidedown. The fact that it was an OPD valve tank did not seem to matter.

Dan

Reply to
dcaster

The valve by design is supposed to turn off due to the internal float. It is designed to save our little skins from the bad propane bottles... :-) Maybe you have one that is not functional.

Martin Martin Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH & Endowment Member NRA Second Amendment Task Force Charter Founder

snipped-for-privacy@krl.org wrote:

Reply to
Martin H. Eastburn

Greetings Martin, After thinking about this a little it seems to me that liquid would come out just fine. When the tank is upright the float rises with the liquid until the valve is shut off. When the tank is inverted wouldn't the float now rise again? Except this time when it rises it is toward the bottom of the tank because the bottom is now at the top. This should open the valve. I guess the only way to test this is to invert my OPD tank with a torch screwed into it. ERS

Reply to
Eric R Snow

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