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From: John De Armond
Newsgroups: rec.outdoors.camping
Subject: Re: Propane refills
Date: Sat, 17 Nov 2001 04:53:19 -0500

Ken wrote:

> Sheesh,
> Considering the cost of materials and the amount of time (my labor and time
> is valuable, too) that is involved in saving about dollar per, much less the
> safety concerns, I think I'll buy new cylinders!

Good for you, Ken.  Seeing that you're a casual user who doesn't
understand the issues faced by high volume users, that is a good
solution for you.  It isn't for me.

Cost is the least of my concern.  (I can fill a cylinder in less
than a minute so my return on my time spent is significant.)
Convenience and flexibility are much more important consideration.

I use the "disposable" cylinders in high volume both camping and
commercially in my restaurant and catering operation.  Their
portability, ease of use, ease of connection and ease of transport
indicates their use where in fixed locations a larger refillable
cylinder would be more appropriate.  Most such uses involve gas
withdrawal at rates that guarantee tank frosting and subsequent loss
of pressure.  I'll cite one very simple application as an example
that even you can understand.

Consider the Coleman Black Cat personal catalytic heater.  I have a
couple of these and we use them extensively for winter camping.
When operated wide open, the gas consumption is such that the
cylinder will start frosting when the tank is about half full.  This
reduces the pressure and therefore the heat output.  The solution is
to use a tank until the pressure drops, then disconnect it and
replace it with a fresh one.  The old tank is still partially full.
At the end of a camping trip, I'll end up with a dozen or more half
empty cylinders.

Now I could just toss 'em.  But I'm a cheap bastard who won't waste
hard earned money.  And I could just juggle 'em around, spending
time warming frosted cylinders and so on.  But the point of
diminishing returns is quickly reached.

The solution I use is to bring home the box of half empty cylinders
and top 'em all off from a 30 lb tank.  I have a bulk fill system
(like they use at the propane dealer to fill your grill tank) so I
buy propane for a fraction of the price you would pay to have your
grill tank filled.  The cost saving AND the flexibility makes the
tiny bit of time it takes to fill disposable cylinders worth it.

I certainly understand that with your casual usage, trundling over
to Wally*World occasionally for one or two new tanks is probably
optimum for you.  I suppose that it is asking too much to expect you
to contemplate that your personal solution isn't a "one size fits
all" for everyone else.


From: John De Armond
Newsgroups: rec.outdoors.camping
Subject: Re: Propane refills...Questions
Date: Mon, 19 Nov 2001 06:48:37 -0500

Randy wrote:

> Does this mean that we have to start watching out for the Propane
> Police everytime we go camping with propane bottles?  And, How does a
> person positively identify a propane bottle that has been refilled and
> transported illegally?  Myself, I would prefer to refill these things
> instead of adding them to our local landfill, since the recycle places
> don't want them.

No.  As a practical matter, there is no enforcement mechanism for
individual non-commercial users.  It shares that in common with a
number of silly federal laws.  About the only way you'd ever get
caught is that if one of your refills was involved in some sort of
accident, let's say, a cylinder leaked inside a car and caused an
explosion.  Even then, very unlikely that your refilling would be
detected unless you damaged the cylinder in a manner that would be

The law keeps someone from setting up a company to refill
disposables of unknown origin en masse.  To that end I suppose the
law does what it was designed to do.

From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Date: Tue, 01 Feb 2005 11:46:05 -0500
Message-ID: <>

On Tue, 01 Feb 2005 11:16:25 GMT, Speedy <>

>I know there was considerable discussion on this topic recently.  I
>didn't pay much attention to it because I've got an extend-a-stay hose.
> I just got an e-sale flyer from Harbor Freight with an adapter for
>refilling the small bottles if anyone's interested.

I fill hundreds of tanks a year in connection with my catering operation.

That type of filler works poorly, if at all.  Holding the cylinder
horizontally both defeats the available gravity boost and obstructs the
safety valve.  Lifting the safety valve with needle nose pliers is vital
to achieving a full fill.

For little more money you can make one that works great.  You'll need a
POL or ACME to 1/4" NPT nipple, a 90 deg female 1/4" NPT elbow and a 1/4"
NPT to disposable cylinder fitting.  All are available at hardware stores
under the Mr Heater brand name.  Simply screw the parts together using an
appropriate thread sealant and use.

Position the 20 lb tank upside down.  Screw in the adapter so that the
disposable cylinder is facing down.  Attach a cylinder.  Open the tank
valve.  When the hissing stops, lift the safety valve with needle nose
pliers.  Continue filling until the first mist comes from the safety
valve.  Remove the tank.  Tilt the tank to about a 30 deg angle with the
safety valve on the lower side.  Lift the safety (wear gloves!) and let
the liquid discharge until it quits.  This leaves enough air space to make
sure the cylinder doesn't hydraulic lock.  Store the cylinder outside for
a day or until you're sure it isn't leaking.  Be sure to let the safety
valve stem snap from the pliers to firmly seat it.  I've found them to be
leak-prone if not snapped.

Best practice is to weigh the cylinder to make sure it isn't overfilled.
A postal scale will work.  Be sure to tare out the cylinder empty weight.

Deep freezing the disposable cylinder and/or heating the source cylinder
will greatly speed the filling and reduce the amount of venting necessary.

I've built an improved system over the above.  It consists of the POL
adapter, several feet of high pressure hose, a POG rated ball valve and
the disposable cylinder fitting.  With this setup I can place the supply
cylinder on a bracket up high on a wall and take advantage of the several
extra feet of gravity head.  As important, with the flex hose between the
cylinders I can weight the disposable cylinder as it fills.  This greatly
improves the uniformity of fill and reduces the chance of an overfill and

With this system and with a warm supply tank, I can usually get away with
not having to vent the disposable cylinder.  This greatly extends the
useful life of the disposables.  I was only getting 4 or 5 refills before
the safety valve started leaking.

The safety nazis have made the task more challenging with the OPD valve.
There is a flow restricter in there that greatly limits the flow, in some
valves, to a mere trickle.  Most of my tanks still have the old style POL
valve because I fill my own from a bulk tank.  For the couple of OPD
equipped tanks I have, I disassembled the valves and removed the
restrictions.  Most of the valve guts are held in place with a circular
snap ring inside the outlet port.  Remove that ring and the guts pop out
under spring pressure.  Remove or drill the flow restriction orifice and


From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: Warning about table-top gas grills and those small throw away 
Date: Wed, 28 Jun 2006 22:20:48 -0400
Message-ID: <>

My page on refilling:

From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: Warning about table-top gas grills and those small throw away 
Date: Thu, 29 Jun 2006 01:37:25 -0400
Message-ID: <>

On 29 Jun 2006 06:24:50 +0200, "Jon Porter" <>

>"Frank Tabor" <> wrote in message
>> bill has found a newer way to fill them.  That Schrader valve works two
>> ways.  Lean the bottle over a bit and press on the pin.  Fill till
>> liquid shows.
>> But wait till he posts and gives you the exact procedure.
>I've thought of that, but wonder how durable that pin is.

Not very.  I used to gauge the fullness of the cylinder by lifting the
safety valve.  About half the time it would take several "snaps" to
get the thing to re-seat and uncomfortably often, it would never seat,
requiring the cylinder to be discarded.

As to pressing the safety valve to open it, I can't imagine how that
would work.  I've removed more than one and knowing how it is made,
the only thing I can imagine making it open by pressing would be to
press it so hard that it distorted.

I have a "Ten Peaks" (Wallyworld house brand, I think) tank here in my
hands and I'm pressing fairly firmly on the safety valve stem.  No
gas.  I'm not going to press on it hard enough to do damage :-)

Someone recommended that while refilling the small cylinder, just turn
the gas on and let the propane flow to the small tank until the sound
stops.  This WILL take the small cylinder "solid" (no vapor space)
unless there is trapped air inside the tank - an unlikely event.  I've
done this more than once by not paying attention to the process.  Just
like overfilling a grill tank, as it warms up the safety WILL lift and
release propane - a very dangerous situation.

I now exclusively use the procedure I detail on my website.  From
experience, I can tell about when the cylinder is about full from the
sound of the flowing gas and the tone of the ring when the cylinder is
rapped with a wrench.  I still weigh each cylinder to be sure.  I
still occasionally overfill one, whereupon I have to bleed off the
excess - wasteful and annoying.  A simple postal scale is more than
adequate for the purpose.


From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: Warning about table-top gas grills and those small throw away 
Date: Thu, 29 Jun 2006 20:26:24 -0400
Message-ID: <>

On Thu, 29 Jun 2006 02:27:40 -0400, bill horne <>

>> Someone recommended that while refilling the small cylinder, just turn
>> the gas on and let the propane flow to the small tank until the sound
>> stops.  This WILL take the small cylinder "solid" (no vapor space)
>> unless there is trapped air inside the tank - an unlikely event.
>No it won't. It'll get you a half-full bottle. Approximately. You
>should know this - it was from you that I learned about using the
>relief valve so that I could do away with the refrigeration step I
>was using to get a full bottle.

Actually it will and I've done it by accident several times.  In the
absence of non-condensables in the gas space (air, CO2, etc), there is
only propane vapor.  As propane is forced into the small tank by the
gravity head and any pressure differential from difference in
temperatures between the tanks, the propane vapor in the throw-away is
compressed.  It heats a tiny bit from the compression and as the heat
is conducted through the walls, the propane condenses. Just like in
the condenser of an air conditioner. If you could view the inside of
the cylinder, the walls would be sweating.  This process continues
until there is no vapor space left.  There is no space left, there is
no sound when the cylinder is shaken and the relief WILL weep propane
as the cylinder warms.

This is a very slow process so you're not likely to have it happen if
you're standing there monitoring the progress.  But if you walk away
to do something else and forget about it for an hour or two, the
throw-away cylinder WILL be solid when you return, assuming there is
no air in it.


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