Newsgroups: rec.autos.tech
From: ghg@noose.ecn.purdue.edu (George Goble)
Subject: Re: Leaking A/C Evaporator Coil
Date: Sun, 30 Jan 1994 11:02:22 GMT

In article <2if0fa$c2d@blkbox.blkbox.COM> sengle@blkbox.blkbox.COM
(Steven W. Engle) writes:

>I just got my Mazda MX-6 GT (88) back from the shop. The A/C
>died in it about five months ago, I figured I better get it fixed
>before the Houston summer arrives.
>
>They tell me the failure was due to a leak in the evaporator coil.
>Does this sort of thing happen that often? A good chunk of the
>bill was labor tearing apart the dash and putting it back together
>again.

This is a common failure. It is very labor intensive to replace
an evaporator.  Dunno why they had to tear the dash apart to tell
if it was leaking.. Sniffers are very sensitive which will find this
leak without ripping it apart (most of the time)..

You may want to check out Cryo-Chem Self-Sealing refrigerant.
(R-12 for your car).  A "kit" is approx $100, you need to change
the drier also.  Trade price on Honda driers are around $25, so
It will be marked up a little.  Call Cryo-Chem @ 1-800-237-4001
for a list of suppliers/repair places in the Houston area which
use the product.

This kit contains a liquid drier, which brings the moisture in the
system down to 0ppm, and a "cryo-silane" sealant, which is air/
moisture activated "epoxy" which circulates with the refrigerant
at a few hundred ppm.

The system must be absolutely dry for the sealant to work.. a drier
change a mandatory, since your system has leaked out, moisture has
gotten in and saturated the drier.  The sealant will pull the moisture
out of the drier and activate in the drier, wasting the expensive
sealant.  No harm comes to the system, but there will be no sealant
left to seal the leak if the system was wet.  The liquid drier
"DRY-PAK", is used to dry out the traces of moisture in the oil, etc,
before the sealant is added.

In normal operation, if the leaking system holds the charge for a day
or longer, then this kit will probably fix it.  The cryo-silane
leaks at the leak site, and hits moisture and air and polymerizes,
sealing the leak.  I have heard of approx 50,000 evaporators 
fixed by this method in Florida.

I have used the Cryo-Chem system extensively in both automotive and
fixed refrigeration with excellant results.  I even know people who
have used it to seal leaking ice-rinks, thus saving digging up
the entire  rink to replace the evaporator.
--ghg

From: ghg@cidmac.ecn.purdue.edu (George Goble)
Newsgroups: rec.autos.tech
Subject: Re: GHG R-406A [GHG R-12 subst] to become legal for cars 9/18/95
Date: 27 Jun 1995 01:02:30 GMT
Organization: Purdue University Engineering Computer Network
Message-ID: <3snlb6$crc@mozo.cc.purdue.edu>
Lines: 29

In article <DAsC9v.9n5@boi.hp.com> wesf@boi.hp.com (Wes Fujii) writes:
>George Goble (ghg@cidmac.ecn.purdue.edu) wrote:
>
>: Right now R-406A is just in 25lb cylinders, but there are plans
>: for 10oz "blow off" cans in the future... 
>
>Will it be distributed in the leak-fixing variety?

GHG R-12 subst was at one time avail with or without
the Cryo-Chem "self-sealing" additive.  

We talked about this question at our lunch refrig mtg
(a coincidence).  This sealant worked very well for
its intended uses..  You can still get it from Cryo-Chem
(1-800-237-4001)

Many people become "scared" when they see additives in
refrigerant, from other past brands of sealants which didnt work.

Also, for Cryo-Silane to work, the system needs to be
bone dry, or else the sealant is wasted (activates in
the drier).. Many service techs are sloppy and dont have
dry systems, which causes corrosion, acids, etc.. and
more business later!

Cryo-Silane is a sealant way ahead of its time.

It is taking all our efforts to do R-406A at the moment,
but we may do cryo-silane in the future sometime again.
--ghg

From: ghg@shay.ecn.purdue.edu (George Goble)
Newsgroups: rec.autos.tech
Subject: Re: Cryoseal refrigerant
Message-ID: <6rp5j3$m31@mozo.cc.purdue.edu>
Date: 23 Aug 1998 13:31:15 GMT

In article <35DEF110.549F@indy.net>, David Wendt  <wendt@indy.net> wrote:
>We own a 1991 Ford Aerostar with two (count 'em, two) AC systems, front
>and rear, both dead.  Firestone wanted over $600 to fix the front one
>only, but suggested waiting until a retrofit for R134 became available,
>probably for about the same price.  However, I found a Web page for a
>product called Cryoseal <www.cryoseal.com> that makes this product sound
>like the greatest thing since toilet paper-- a direct replacement for
>either R12 or R134A that seals leaks, eliminates moisture in the lines,
>and works as well as or better than the original, but at "generally less
>than one half that of component replacement".  Has anyone had any
>experience with this product?


Try www.cryochem.com.

This stuff works.  It is "gaseous" epoxy, that forms a hard seal at
the leak point when it sees moisture and oxygen.  It will not stop
(bit will slow down) compressor shaft seal leaks.. also it may not
always work on old rotted hoses.  IT is good for evaporators, metal piping
and condensers..  It is about $100/kit.  System must be "dry", or
the sealant activates in the dryer, wasting it, but not hurting
anything.  Unless known dry, the dryer should be changed first.
They first charge in something called "dry-pack" to convert any
remaining moisture to silicone oil before adding the cryo-silane.

Back in 1993 we made a version of "Self-Sealing" R-406A with
premixed dry-pack and cryo-silane.  IT worked well, but was too
expensive for the general market.  If you have any questions,
you can call JJ Packo, the inventor, at 1-800-237-4001
--ghg