Red Tek

[Spittybug]

I had to get some caliper seals from DMCH today and ran into Stephen. We started talking AC and he told me that for about 4 years now they have been putting Red Tek into the R-12 systems with great success. Very cold, works with old system and simple to do. I'm looking for anyone that has done it to their car and see what they think of it. I've done some researching and it seems like pretty good stuff. I know I have a slooow leak in my system somewhere, most likely schraeder valves, so a can of their leak stopper is probably in order too.

Feedback? Thanks.

[Ron]

I've had several come through the shop with Red Tec in them. It does very well, if installed in a flushed system. Two things I have against it: bad documentation and all of the pressures change, making the diagnostic charts almost useless (as would anything but R-12.) But even then it's not a big problem unless you are pushing/tweaking one for an extremely hot area.

If you do this, ignore where the docs say charge at 0 pressure and charge as liquid (if using the port at the compressor...can lock down the compressor).

[Spittybug]

I'm thinking this is a good option at this point. R134 needs new hoses, new condenser, orifice tube, compressor... to do it right. The Red Tek route looks low risk given that if it doesn't work well enough I haven't spent any other money on hardware. Stephen was really excited about it and told me how easy it was to do myself, so not like he was selling it to get me to come in and have it done. He did mention filling it very slowly for best results. Also said NOT to pull a vacuum on it; just put it in an empty system. My R-12 has all gone, so no problem there....He also said the leak stop stuff was very effective for the minor leaks I must obviously have.

I'm not sure I understood your last comment Ron??

[Ron]

The Red Tek docs say to charge at 0 pressure = no vacuum, which is what Stephen was saying. This is incorrect and Red Tek has it "slated to be removed from the documentation". Read it closely and you will see it is contradictory unless you allow air/?? into the system after pulling a vacuum, which you should never do. As Stephen said, you should add it (or any other) in slowly on a D or any other system where the low/suction port is located close to the compressor (or go to the accumulator,...). This is because liquids do not compress and it will lock down the compressor/break something.
(As I understand it, they say to use use liquid to get the intended blend... Now if you could charge liquid and were using the little cans, the amount it would be off (left in last can) wouldn't be significant.)

IMHO: AC stop leak is 1:10 at best - and that is the high dollar stuff.

[DMC-81]

Because your old refrigerant is gone, and you only have a small leak, I would definitely recommend changing the Schrader valves and as many O-rings as you are comfortable with ( i.e. The hose connections are not rusted too bad or otherwise deteriorated so that you'll risk sealing it again.), before you pull vacuum and recharge. The required parts are pretty inexpensive.

I didn't do Red Tek but I still have the original system, hoses, etc., and that's what I did. Mind you I did other refurbing work on the compressor and the accumulator, but the point is I got the 37 year old system to be tight enough to hold max vacuum all night.

If you want to go this route, I have a thread with parts and process that I can share.

[David T]

Do not use the plastic dust covers on the service (shrader) vales. Get some brass caps with "O" rings in them and just replace the shrader cores. Make sure you use cores for A/C NOT tires. As for small leaks, leak sealer is OK but it won't fix a leaky compressor seal. Not familiar with Red Tec but IMHO all of the "replacement" refrigerants are blended and do not perform as well as R-12 and have limitations on "topping off" so you cannot just add a little if some leaks out. You can still get R-12 and even though it is expensive, it is not so bad, even if you have to add a few ounces every year. It is still the best refrigerant to use in our systems.

[adam_knox]

I can't speak to maintenance of Red Tek, but i can tell you its in my car, and it is cold. Keeps me cool on humid Wisconsin afternoons. I usually have to drive with two layers for work (long sleeve shirt and undershirt) plus pants and if its properly charged it works well enough for me.

Sent from my SM-N910P using Tapatalk

[DMC1890]

I'd like to see the feedback you get. I'm also in Houston, and I'm hoping to get 1890 running again 'real soon now' after 8 years. I don't like what I read about R134 conversions. I'm considering doing the Red Tek myself, but if DMCH will do it, that's an interesting option (assuming I can survive the 20-minute drive in this heat!).

Robert

[opethmike]

I used RedTek in my former 1987 Esprit. It worked nicely.

[81dmc]

I've also talked to Stephen about Red Tek. Looks like a great R12 replacement, but it seems like a hard to find product if you ever have to recharge on the road.

I went with R134a for the ease of maintenance and low cost. My vent temps were never great on 12 to begin with, so I never lost anything. Lowest temps I've seen from vents with a knockoff SD 7H15 and a parallel condensor was around 65 Fahrenheit.