Posted by George Goble on October 22, 2000 at 11:52:19: via: or 206.230.0.138
Year: 1978
Make: Datsun
Model: 810
High Side: 250
Low Side: 30
Refrigerant: R12
Outside Temp: 80
I have followed the posts on Cliplight SSP sealing refrigerant
with interest.
Background info. In 1990 I invented GHG-X3, which became known
as "GHG Refrigerant-12 Substitute", then as "Autofrost", then as
R-406A after we get classified by ASHRAE, which is a blend to
replace R12. (GHG-X1 was 60/40 propane/isobutane, and we never
sold that, but guess what started off the HC guys). I also invented
GHG-X8 (Cooltop) refrigerant and others.
Since the early 80's I have known JJ Packo, inventor and patent
holder of the Cryo-Chem family of "Self-Sealing" refrigerants.
My 1978 Datsun 810 developed an evaporator leak around 1982 or so.
At first, I ran small tubing (1/8" copper), and put a manifold and
dry-eye in the passenger compartment.. and drove around with a 30lb
cylinder of R12 in the back seat.. and when the system got low,
just opened up the low side manifold valve and put in another
pound of 12 while I was driving! Hell, a 30lb cyl of R12 was
only $30 back then and lasted all summer! What ozone hole?
When fully charged, and hot, it lost about 1 pound/week.
I met up with JJ packo around that time.. my home central A/C
(R22) had started leaking about 1-2 lb/month (4 years old)...
They had a SSR12 "kit", that was two cans of R12, one with
some "dry-pak" dissolved in the R12, and the 2nd with some
cryo-silane (gaseous epoxy) dissolved in the R12. Kit was about
$100.
Instructions, were to put on a new dryer, and change the
orifice tube (this car had an exp valve).. I didnt change
the dryer, but did a 10 min vac, charged in the 1 lb can
of dry-pak (about 2% drypack conc, rest is R12), put in a
can of R12 (now at 2/3 charge)... and ran car for 1/2 hour
to circulate the dry-pak, which converts the free moisture
into silicone oil (so it doesnt form acids anymore, and in
this case, removes the moisture, so the cryo-silane wont
activate).. Next added the Cryo-silane (about 3% cryo-silane
conc in 12oz of R12), and now at full charge..
for a couple of days, I noticed the cryo-silane "dead fish" odor
when starting up the A/C.. (evap leak), and after two days,
odor was gone.. viola.. it worked.. self-sealed the evap leak!
and it held.. that car never leaked again..and in 1990 it became
the "development" car for GHG refrigerants... GHG-X1, X2 (HCs),
GHG-X3 (R-406A/Autofrost), and GHG-HP. in 1993, the fuel pump
died (but the A/C still worked), so I had the car junked then.
IN 1982, my house central A/C (heatpump) was leaking about 1
pound/month of R22 (inside coils). I put in an SSR-22 "kit"
(same dry-pak and Cryo-silane, but dissolved in R22 instead)..
That system didnt leak for the next 18 years!
[noticed that Cliplight SSP states to not use it in electric driven
compressors - HVAC, probably since it's drying agent it methanol?]
In the early 90's we experimented alot with Cryo-chem's system
in both cars and stationary HVAC systems. One thing we learned
(Cryo-chem stated this) was to remove/change the dryer out.. since
a water logged dryer, would just cause the drypak and sealant to
become used up and activate inside the dryer, wasting it, but it
didnt clog up, but did not seal, since moisture used it up by
making it activate inside the dryer.
It was better to REMOVE the dryer completely (suction filter only
ok), than to put in a wet one.. Lots of automotive dryers come
already wet, and this hurts the sealing process. Cryo-Chem even
had some Florida company made "blank" automotive dryer shells,
that had no desiccant bags in them, for use with the SSR system. GM
got really ticked at SSR, since they "lost" the sale of over
50,000 replacement evaporators in florida alone.
Used properly, in a non water logged system, the Cryochem system
would self-seal evap/condensor leaks upto about 1 pound/hour and
stay in the system and fix newly forming leaks.. It would slow down
(i.e. during the winter) shaft seal leaks, but would not stop
them since it was a moving part. Most of the time, "hose permeation"
didnt seem to hold, since the hose "puffs up" when pressurized and
breaks the seal.. some thin aluminum condensers did this also, and
would unseal from physically puffing up during pressure changes..
On evap and condensor, metal pipes, it worked 95-98% of the time well.
(R12/mineral oil days)..In a few cases, very extreme cold, could
make an evap self-seal fail due to extreme contraction (-30F temps),
but it often self-sealed again, with only 1/2 lb of charge lost.
(customer noted dead-fish silane odor on -30F day).
ALso, on very old, abused stationary compressors, that had been
run low on charge a long time, caused the motor winding insulation
to "fry", would end up with a motor burnout when brought back
up to full charge and the silane was added... Hermetic compressors
rely on correct superheat (need cold suction return gas) to
properly cool the compressor motor windings).. and years of running
low could damage the compressor windings first... Gently adding
the silane to the high side, highly diluted still allowed alot of
the older compressor to work, without causing a motor burnout.
An early version of GHG-X3 was even marketed as "self sealing
GHG Refrigerant-12 Substitute" back in 1993/1994... but the drypak
and silane had to be both mixed in with the refrigerant.. This lower
the cost alot.. but also the effectiveness, since the dry-pak did
not get a 30 min head start to scavange moisture before the sealant
hit the moisture... This system works like the Cliplight, where
once it leaks out, and sees moisture and oxygen, it polymermizes
and seals, but it seems to be able to handle much bigger leaks..
I also noticed from your posts, that the CLiplight SSP system, that
both components seem to be added at once to a system with no charge
and the system charged, rather than running the system at partial
charge with the drying agent first to scavange moisture... also
nothing said about changing dryer or orifice tube for the SSP.
The self-sealing GHG-X3 had much better luck in stationary systems
that had no water logged dryers in them.. but in the end, having
a sealant in the system, just scared too many folks, so we discontiued
it... It worked really well if used properly...
For Autofrost, we tell users to buy the Kit from cryo-chem, so
the dry-pak can be added first to pre scavange moisture, and it
works better than having it premixed in the refrigerant.
Now, with the R-134a AGE, and Hyper moisture grabbing PAG oils, I
dunno what will happen (cryo-chem has SSR134a kits but I havent
done much with them). We buy the conc drypak component and add
a small amount to GHG-X8 (cooltop R-134a substitute refrigerant)
to knock out moisture there (no sealant though)...since we see so
many already wet R-134a systems, that anybody adding Cooltop (with
no dry-pak) would
likely see their evap acid eat out in a year or so and blame it on
us... If they had added 1 can of Dry R-134a instead, system is
wet enough already, the same evap leaks would still happen from
acid eatouts... but customer will not understand that... so we
have to have a drying agent to just get a level playing field..
Brand new, unopened PAG oil from GM, has been sent to a lab for
testing and came back at 800-900ppm moisture range! Standard for
refrigerants is 10ppm.. and anything over 50-100ppm will start the
acid corrosion/eat out process going...no wonder so many 134a
systems start leaking (PAG oil)... maybe it was intended? trade
for a new car?. See
http://www.autofrost.com/wetpag.pdf
for the lab test results..
JJ packo originally invented the SSR self-sealing system while at
NASA in the 1970s.. to seal aircraft fuel tank leaks, after mfgr
and has adapted it to refrigerants. Overall, (Before Cliplight -Jury
still out on that one), that the cryochem system was the only one
that really worked, but it had to be properly used, and still
had several limitations, as mentioned above.. Also severe vibration
cracking open a liquid line (like SSP test case) will also fail
on the cryo chem system. JJ Packo passed away earlier this year, but
the company continues on. Their web page is at www.cryochem.com
(on same server as www.autofrost.com - "worldserver.com"). I have
tried to present an honest and unbiased view of my experiences, so
they may benefit others down the road.
O well enough rambling on my experiences with self-sealing
refrigerants...
--ghg