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From: John De Armond
Subject: Re: What about an electric grill?
Date: Tue, 25 Apr 2000 01:59:40 EDT
Newsgroups: rec.outdoors.rv-travel

DsrtTravlr wrote:
> >
> >Not to be testy, but, the bottles say, "not refillable."
> >You say, "learn from instruction or directions.."
> >Which instructions were you following?
> >Does anyone have a source for the small bottles that are designed for
> >refilling.?
> >
> The NOT REFILLABLE designation is to state that they may not be refilled
> commercially.  If they were not to be refilled by the user, products to
> refill them would be illegal, and you could not buy them from major
> companies.
> (Cabela's, NorthernTools, Walmart, Grainger, et al.)
> I believe that if there was any danger especially in our sue happy
> society, they would drop them like a bad habit, but on the contrary,
> they have sold them for years.

What it really means is that if you refill a disposable cylinder AND
you transport it on federally funded roads (read: all roads) AND you
get caught, you are subject to up to a $10,000 fine and 5 years in
Camp Fed.

There is part logic and part politics to this DOT rule.  The
politics are, the disposable cylinder manufacturers don't want the
competition. Go research the federal register oh, about 40 years ago
if you don't believe me.

The logic part is that these cylinders do not have the safety margin
to withstand much internal rust.  The propane put in the cylinders
at the factory is dry.  The propane you buy in your grill tank
usually is not.  In fact, fuel grade propane is usually nearly
saturated with moisture.  If your refilled disposable cylinder rusts
from the inside out, where you can't see it,  you might be in for a

The federal Gestapo probably isn't going to kick in your doors over
this (OTOH, with Janet the Butcher of Waco at the til....) but if
you are involved in an accident or cause a fire, you might find it

This same issue is of much more concern with freon tanks converted
to air tanks because compressed air is always wet unless dried after

I refill my cylinders too, but I don't keep one very long and I do
check for moisture in the propane I use to fill with.  I have an
Alnor dewpoint tester; most people don't.

From: John De Armond
Subject: Re: What about an electric grill?
Date: Tue, 25 Apr 2000 14:22:24 EDT
Newsgroups: rec.outdoors.rv-travel

Jvcarolyn wrote:
> I do not know where you got the information about some propane being
> "wet"? The propane I fractonated from natural gas the last 30 years was
> always completly dry. Several steps are taken at the refinery to assure
> it is dry and several tests are performed to allow it to be shipped.
> Your informaiton is news to this gas plant operator and supervisor.
> Now, if they mix butane with the propane for this canned fuel, maybe it does
> become "wet" as butane is not dried as propane is.
> Interesting,
> J.V.

I >know< that it is wet because of the water/odorant/muck I
occasionally had to drain from my storage tank when I owned a
company that sold propane.  I also >know< that it is wet due to the
rather extensive testing I did on propane  trying to find an
inexpensive source for propane suitable to use for refrigerant when
I was working on developing an alternative to R12 refrigerant. 
Every single source of fuel grade propane that I tested with my
Alnor dewpoint tester contained a large moisture content.  I ended
up buying process grade propane which was dry because I spec'd it

I was >told< and warned that propane would be wet in the mandatory
state conducted class I had to attend before getting a dealer's
license.  We were told that in the context of justifying frequent
internal inspections of propane tanks, AKA "visual hydros".  I was
>told< in that class that the reason propane is wet is that the pipeline
flow is buffered in floating tanks that float on water. I have no
independent confirmation of that fact (not a major issue in my life :-)
but it makes sense since natural gas is buffered in the same sort of
tanks.  I was also >told< in that class that propane dealers often (now
illegally) transport anhydrous ammonia fertilizer in their trucks during
the summer and that some dealers were known to wash their tank trucks
afterwards to try and remove the evidence of ammonia.

I make the distinction between what I know to be true and what I was
told to make the distinction and to illustrate that what I was told
and what I know from experience is the same.  I never ran into
ammonia-contaminated propane but it was a frequent problem according
to a an industry newsletter I received at the time.  

I have no doubt that propane is dry when it leaves the refinery. 
Things happen on the way to your burner, however.


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 13:37:32 -0400
Message-ID: <>

This isn't all that uncommon these days, unfortunately.  Usually if
you operate the valve in the tank neck again, it'll seat.  I typically
bounce a small Phillips screwdriver off the valve pin.  That
momentarily opens the valve and then lets it quickly snap shut.

My theory is that some sort of crud get stuck under the valve seat.
That theory is reinforced by the fact that Mr Heater now STRONGLY (in
big red letters) recommends using a propane filter in line with their
portable heaters.

The quality of propane in throw-away bottles has declined over the
past few years.  I use it as a refrigerant (almost equiv to R22) so
purity and dryness matters.  I used to could rely on throw-away
bottles to be quite clean and dry but no more.

This is one of those "grin'n'bear" it situations, I suppose.  If
you're very concerned about leakage, you can get a mating connector,
Mr Heater brand", that goes from the throw-away to a male 1/4" NPT.
Put a 1/4" NPT cap on that and you have a cap that you can attach to
the cylinder when not in use.  I'd want to do this instead of leaving
it attached to the grill because the grill valve could vibrate or be
knocked open.  All the big box stores, Ace, Northern, etc, carry the
adapter fitting.


On Wed, 28 Jun 2006 08:14:42 -0400, Lee <>

>During my last trip I visited the Stephen Foster Memorial Park
>and while there I used the grill outside and on this trip I
>found out something that made me a little nervous.
>I had just finished using the grill and was getting ready to
>put it away after disconnecting the bottle from the regulator
>when I thought I heard something, I put my ear near the bottle
>and found it to be leaking.  The only reason I even was even
>suspicious is my last bottle did not seem to last very long.
>So I tested it again and yes after removing the small bottle
>the latest bottle leaked when I unscrewed the regulator, so
>if you store them after using them be sure to leave the
>regulator on them and don't store them anywhere near anything
>that could possible ignite the gas leaking from one of them.
>I consider myself very lucky to have found this out before
>anything happened.  Don't know if this is a fluke or what but
>2 bottles apparently have leaked so I figured I would pass it
>on for what it is worth.  The bottles were Coleman.
>Lee (in Florida)

From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: ## Anyone got a ZODI tent heater ("hot vent") or similar device?
Date: Thu, 22 Jan 2004 16:56:18 -0500
Message-ID: <>

On Wed, 21 Jan 2004 21:51:08 GMT, "David" <> wrote:

>    Regardless, Mark said that the 16.4 ounce propane cylinders use a
>different thread (7/16", 28 threads) than the K28 (probably 1/2", 20
>threads).   Mark does not believe that there is an adapter which can be used
>so that K28 equipped canisters can be used with a gas appliance designed for
>the 16.4 ounce propane cylinder sold by Coleman and other vendors.   Even if
>you were to get a machinist to make you an adapter, there could be other
>safety issues, such as tiny nicks in the threads causing a leak.

The American disposable cylinder interface seals around the valve depressor.
A secondary seal is the rubber gasket that seals to the face of the threaded
valve body.  It is not necessary for safe operation as long as the valve
depressor is not damaged.

Mechanics are not the issue.  The incompatibility is with the fuels.  At 70
degrees propane has a vapor pressure of about 120 psi.  Butane is <30. (too
lazy to look it up.)  At 40 deg propane's vapor pressure is about 70 psi while
butane's is near zero.  The 20% propane mix will be higher but not enough to
properly operate an appliance designed for propane.


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