Ask the Master Auto Technician
I've been researching on best method of restoring my old R12 AC. I don't want to do an r134a retro since it has obvious problems such as being incompatible with mineral oil and grinding your compressor into scrap metal. I was thinking of just getting the leaking line replaced and having it charged with R12 (since your place does carry R12 and recommends it). But I ran across an article about a new refrigerant that is compatible with mineral oil, supposedly more efficient at removing heat than R12 and completely compatible with the older systems. So I figured I would ask you. Not sure if you covered it on your radio show, my schedule changed and I can't hear it as much as I used to.
I like the older systems still. Too bad a newer R134a couldn't be retrofitted to use the old R12 or something better. BTW, my vehicle is a 1985 Buick Somerset Regal, 2.5L. You did a test drive on it before and some repair work.
I trust your opinions on this the most and won't buy another car without your center going over it. And thanks for help eliminating the 20w50 heavier oil is better myth.
I have read the same articles that you have read about this "blend". The EPA rules are this: You must have specific designed Schrader valves for specific refrigerants.
That is why the ones for 134A and R-12 look different. It is a violation of federal law for a shop to install this refrigerant without specific Schrader valves, which are specific for this refrigerant. The shop selling/installing this product must also have a dedicated recovery machine for this refrigerant. Most shops can't or won't pay for this added expense.
The other reason I don't like to see this refrigerant used is due to it contaminating refrigerant recovery units when repair work is necessary. If our A/C identifier says it is anything other than R-12 or 134A we must classify it has "other”. (According to federal law and state law) And "other" is considered a hazardous waste and must be collected and disposed as such. And that is a different story by itself as well as expensive.
My best advice is to fix it correctly using the correct repair procedures and the refrigerants made for your car A/C system. It’s cheaper in the long run, when you do it "right the first time!"
Thanks for writing,
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