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From: (George Goble)
Message-ID: <5tsnlq$>
Subject: Re: hydrocarbon blends r-12,r22 alternatives
Date: 25 Aug 1997 19:50:18 GMT

In article <5tq76s$d7n$>,
>does anyone have the correct percentages for blending hydrocarbon gases
>as alternatives r-12 r-22 r-502 etc. i am told that they are widely used
>in europe and are marvelous please dont tell me about ec-12a or ec-22a
>whereas i am not interested in paying a 1000 % markup. i am certified
>universal by A.C.C.A.

It is illegal to replace HCFC/CFCs with hydrocarbons in the US in
all but a very few limited applications (e.g. oil refinery compresors).

R-12 -> 60/40 (weight) propane/isobutane
R-22 -> 100            propane
R-502 -> unsure.. but maybe propylene or blend of propane/proplyene or
         about 90% propane, 10% CO2 or ethane.

BBQ grade propane is often "wet" and may not be 100% propane, but
may have some isobutane or butane, esp down south to keep the
pressure down.  If no HCFCs or CFCs or HFCs are present, small moisture
like < 200 ppm will not cause problems (unless super low temp).. If
fluorocarbons are present, then you should be < 10ppm moisture to
prevent them breaking down to acids. Use a refrigerant moisture
indicator, and dryers.  We have seen propane at around 30-50 ppm

You may design "new" equipment with proper explosion proof
contactors, vented to the outside, and get UL certification
for flammable refrigerants I suppose..

From: (George Goble)
Subject: Re: Freon R12 Regulation
Message-ID: <>
Organization: Purdue University Engineering Computer Network
Date: Thu, 23 Jun 1994 10:23:04 GMT

In article <>
(Green Eric L) writes:

>In article <>
>(Dave Williams) writes:
>    The iso-butane has become a problem.  I haven't found any anywhere, and
>   I've looked in four states.  I can get it at laboratory supply houses in
>Interesting. Have you looked under "Gas-Liquefied Petroleum-Bottled & Bulk"
>in your Yellow Pages?
>Eric Lee Green     (318) 984-1820
>        P.O. Box 92191  Lafayette, LA 70509

Try Phillips-66, Borger TX. Use grade "Pure" (99.0% purity)..
They used to sell it in 115 (approx) lb cylinders, also an
approx 250lb cylinder.  Camping stores here used to (or still do)
carry isobutane stove fuel..Gallions in Indy has it also..
Watch out, as most fuel is "butane" or "butane/propane" mixtures.
You need isobutane (B.P. 10F) instead of butane (B.P. 31F), since
the latter may not boil off and may return and "slug" the compressor,
busting the valves.

X-Source: The Hotrod Mailing list
Subject: RE: Re: dem ol' air conditioner blues
Date: Thu, 30 Jun 94 07:46:12 GMT
From: emory!!dave.williams (Dave Williams)
Posted-Date: Thursday, Jun 30 1994 03:46:06

-> OK, I'm sure I have it writen down somewhere... but, what is the
-> correct mix of propane and isobutaine?

 It's in the general vicinity of 78% propane 22% iso-butane.  I'd have
to look up the exact proportion.  George Goble says it's not completely
critical, but closer is better.

->  How do you use the stuff?

 It's supposed to be a drop-in replacement.

-> Can I use propane gas?

 Plain old propane (George calls it "hamburger gas") will work, BUT:
around here, anyway, when you have a propane bottle refilled, you might
get 100% propane, 100% butane, or any crazy mixture of anything gaseous
the place has on hand.  I'd recommend paying a little extra for propane
torch or camping fuel with an MSDS sheet that says "propane."  You only
need part of one small bottle, after all.

->  How well does it work?

 It's *supposed* to work just fine.  That's the idea of a drop-in

->  Do I need to change oil?

 No.  Again, another advantage of a drop-in.

-> Easer question:  I'm willing to look around at camping stores for you
-> guys for isobutaine, but what should I ask for?  Camp stove fuel?
-> What should it say on the can?

 There are three types of camping fuel - propane, n-butane, and
iso-butane.  I spent quite a bit of time calling places, carefully
asking for iso-butane, being told it was in stock, and being offered
propane when I got there.  I offered to introduce one clerk's face to
the wall after the fourth or fifth time.  If you can actually find
butane, the most common is n-butane.  What you want is iso-butane, which
is sometimes sold as "high altitude" camping fuel.  The difference
between n-butane and iso-butane (as far as refrigeration is concerned)
is that the iso-butane has a lower... uh, boiling point, I think it was.

 I have a ton of data on this stuff and would be happy to write a short
FAQ on it, except I want to actually DO it first, but I'm having a hell
of a time finding any iso-butane.

 BTW, does anyone know of a convenient source for buying those oddball
not-quite-Schrader-valve AC fittings?  I managed to scam one off a junk

From: (George Goble)
Message-ID: <4n8ojt$>
Subject: Re: How to get freon / pe
Date: 14 May 1996 01:45:33 GMT

In article <> (RICHARD ROSS) writes:

>Does anybody still use Freon anymore?  I thought most people had 
>switched to the 20% isobutane 80% propane mix???

[20% isobutane / 80% propane is ILLEGAL in the US to replace R-12 in cars]
[60% propane / 40% isobutane works better.. pressures are correct.. but
still illegal in the US under current EPA rules]

>While we are on the subject, has anybody found a good source for 
>isobutane?  i've been buying the MSR stove fuel at a camping store for 
>$3.00 / 6 oz can.  works ok and i only use 2 cans for a complete fill up 
>but it should be a lot cheaper if i could buy it in bulk somewhere like 

Try Phillips-66, Borger, TX.. R-406A and GHG-X4 refrigerants use 4%
isobutane for oil return (still nonflammable).  They use grade
"PURE" isobutane.. around 99.0% purity (impurities are neighboring
hydrocarbons, not moisture).. no "odorant" or "stink".. Avail in
containers around 116 lbs, and 244 lbs.. Next size up is a tanker
truck (about 6,000 gallons).  Valves are CGA-510, same as the BBQ
grill tanks..  It takes FOREVER to suck those (244 lb size) dry
thru those tiny valves, even with rows of 'em lined up, manifolded

There is an "instrument" grade, which is think is 99.5% pure, but
it costs a fortune... 99.0% is good enough for refrigerant.

--ghg, Inventor, R-406A, GHG-X4

From: (George Goble)
Message-ID: <4g1okm$>
Subject: Re: propane as substitute for freon?
Date: 16 Feb 1996 11:09:10 GMT

In article <4g03tg$> writes:
>: a mechanic friend insists that he knows a farmer that contends that 
>: he has been using propane in his tractor air conditioners as a 
>: replacement for R-12 for years with no side effects and presumably 
>: it cools.  any comments?
>Comment:  an underhood propane leak could be disasterous if the
>          leaking propane ever ignites.

The amount of charge in the A/C system is tiny compared to the fuel 
carried on board (either propane or gasoline).  Fuel lines can break also.

Using propane (in all but a certain few limited industrial applications)
is now ILLEGAL in the US for a refrigerant.  You will incur the wrath/fines
of the EPA if you get caught. Fines can be as much as $25,000 with
up to $10,000 "rewards" for turning in people.

Pressures of pure propane are too high for R-12 replacement, but
propane almost exactly matches R-22 pressures.  One might be able
to get by with an extreme undercharge in the A/C system.  If
his tractors had large condensers and good airflow, he could probably
get away with it.  Also the farmer may be using "LPG", which may
be a blend of propane and isobutane to start with.  60/40 (by weight %)
propane/isobutane is the ideal blend to replace R-12.
Provided the pressure-temperature curve is close, hydrocarbons 
(propane/isobutane) have excellent miscibility in mineral oils used
in R-12 systems, and are excellent refrigerants.  They are
however, extremely flammable and this risk must be evaluated
(for those  outside the US whom may want to use hydrocarbons)
on a case/use by case basis. For automotive use, it is generally
agreed on that the worst case scenarios are wrecks, which rupture
the system + electrical system shorts, for risk studies to begin with.

Many of the crowd whom screams "flammable .. explosive, etc"
on hydrocarbon refrigerants have major vested interests to
lose if hydrocarbons ever came into widespread use (like Europe
is doing now).  It costs less than $.50 to recharge a system,
no ozone depletion, no global warming.

It seems that all too often  risks are evaluated by "vested interests"
instead of by unbiased scientific methods.  

But..Some service shop can't stick you for $300 for a R-134a
recharge if you used hydrocarbons, nor will a large auto
maker sell you a new car (combine/tractor?) so you can get
a new R-134a A/C.  The Chemical & refrigeration industries have
invested billions of $$$ in R-134a, oils, etc... and using
propane/isobutane cuts them all out of the loop.
You know how this country works.. go figure...

--ghg, inventor of R-406A & GHG-X4, R-12 drop-in substitutes

From: (George Goble)
Message-ID: <4g5507$>
Subject: Re: propane as substitute for freon?
Date: 17 Feb 1996 17:58:31 GMT

In article <> (Steve Wright) writes:
>In message <<4fo0em$>>  writes:
>> he has been using propane in his tractor air conditioners as a 
>> replacement for R-12 for years with no side effects and presumably 
>> it cools.  any comments?
>The temperatures and pressures for Propane comared to R12 and R134a are
>very similiar.  I don't know what the moisture content of heating
>propane would be but it would need to be extremely low to use it in an
>airco system unless you were prepared to change the filter/drier a few
>times to get it cleaned up.

Moisture is a valid concern.  I measured some propane around here, and it
was 30-40 ppm moisture and that would probably work.  Install a
"dry-eye" on the system, so you will know when it is over 10-20 ppm
moisture.. I bet a medium sized refrigeration drier (16 cu in) would clean
that up fine, as they can hold 150-250 drops of water.  If there are
no HCFC/CFCs in the system, a much higher moisture content can
be tolerated (upto about 1000ppm) at which point the water may
freeze in the expansion device.

Propane has too high pressures for R-12/R-134a systems.. YOu need
to use 60/40 (by weight) propane/isobutane to get the correct
pressures for an R-12/R-134a system.  You can probably get isobutane
as camping fuel.. dont use "butane" (n-butane), since it boils at
31F.. way too high.. i-butane boils at around 10F, propane is -44F.
Sorry about the non-metric units.

Pure propane is a direct match for R-22 though.

>I have a mate who is adding a heat pump to his home co-generation system
>using automotive parts and he plans to use propane as the the
>refrigerant. I'll report back when he gets it running.

His heat pump is probably designed for R-22, so propane should
work fine there (this is in NZ, not the US, it is illegal here 
to do that now), I had a friend of mine charge 3 R-22 window A/C
units with propane back in 1990 (when I was inventing R-406A),
and they are all still working just fine.

Be very leary about using an automotive compressor for
any long term "stationery" duty.  They are not built to
last.  Most cars will have have 3 to 6 months of "run time"
on a compressor during the life of the car.  My home heat 
pump is 18 years old, runs summer & winter, still original
(Techumsa ?) compressor.  Stationary equipment is buillt
an order of magnitude better.  Try to find some open drive
belt driven R-12 compressor, or better an R-22 compressor
and use that instead.  You can use an R-12 compressor for
R-22 (or propane) service if you reduce the operating
speed to 3/5 of what the R-12 speed should be.

I have heard occasional concerns (other than flammability) from
researchers that propane may thin the oil and some heavier oil
might be needed..

DO NOT TRY TO USE PROPANE as a refrigerant in the US
as it can be a $25,000 EPA fine and a $10,000 "reward"
for the person whom turns you in. Propane is also known
as "R-290" and isobutane is "R-600a"

--ghg, inventor R-406A & GHG-X4, drop-in substitutes for R-12.

From: (George Goble)
Newsgroups: sci.engr.heat-vent-ac
Message-ID: <3t4kct$>
Subject: Re: R-22 replacement?
Date: 1 Jul 1995 23:06:05 GMT
Lines: 18

In article <3t3vvq$> (Ed
Pearlstein) writes:

>    Is there a drop-in replacement for R-22?  If so, can it be used to
>"top off" a home AC that has R-22 in it?

Propane.  But you must assume the responsibilty and liability for
the flammability. I friend of mine has run pure propane in 2 or 3 
window A/C's for 4-5 years now.. still running fine.
A typical split home system holds 5lb of R-22, which is equiv to
around 2.5lbs of propane..  How many people get nervous with
3 1lb propane torch gas bottles in their garage?
Make sure you put a drier on or dry it first. Most propane is slightly

The averge female might have almost that much propane in the
propellants of the various products she has in her bathroom.

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