I'm with Larry on this one. Even R12 is cheap compared to the rest of the A/C parts that you're going to contaminate with alternate refrigerants. And the risks involved with flammable refrigerants are just not worth the few bucks saved.

As for reverse converting and acid production, that's why you flush thoroughly and vacuum for a long time.

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Rick Miley
2014 Tesla Model S
2018 Tesla Model 3
2017 Nissan LEAF
Former MB: 99 E300, 86 190E 2.3, 87 300E, 80 240D, 82 204D Euro
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