Flushing Solvent

[Anony55]

I've heard a lot of different recommendations concerning what flush solution to use. Many have said all kinds of "off the shelf" solvents like denatured alcohol, paint thinner, acetone, etc. Then others have said to never use those, but rather, only use products that are designated as ac flush solvents or solutions. The Four Seasons flush video on Youtube is an example of the latter.

Most of the time, when "official flush only" warnings are given, they aren't followed by a reason. So as a DIYer trying to make the best decision possible, it's hard to tell what motivates the "official flush only" position... trying to sell their own flush solutions... industry standards habit... or genuine concern that the DIYer doesn't cause harm or create the conditions for failure.

With flush solvents being so costly (like Dura II being more than a dollar an ounce), the temptation for a more economical path is high. I have thought about a method that might be the best of both worlds, and would like to hear opinions about the idea. I know that others have thought of this. In fact, I've seen this exact idea used by a member of this forum (but no success/failure follow up posting). No one commented in that thread about this particular technique that was done, so I'm asking now in this thread...

Specifically, would it be okay to flush with denatured alcohol until the component is completely clean (by observing the condition of the exiting liquid), and then follow up with a normal official ac flush solution (such as Dura II, or others) to remove any undesirable effects of the denatured alcohol?

Would this would allow for a more economical substance to "do the heavy lifting", but still leave the component with the absolute cleanliness that all the professionals recommend? Good idea??

[Anony55]

Tim, thank you for your recommendation. The HECAT pdf is also very helpful and great information to have.

Even if my idea wouldn't be your first choice... do you have an opinion about denatured alcohol, followed by a bona-fide flush solvent? Keep in mind, I ask the question in the context of everything else being equal, with the only change being denatured alcohol followed by whatever flush that you might normally use.

Thanks

[Avanti Ron]

As a follow up question on an old thread:
I have an originally R12 system that had a leak, and am converting to R134A. No compressor failure ( Harrison A6, 65,000 miles) I purchased flush off of eBay and it is actually flush solvent for machines to prevent any sealers from bonding to the flushing machine's internals.

Will this work, or should I bit the bullet and purchase a different solvent?

Ron

[Tim]

There will always be a debate on what's best compared to the cheapest method. Just like anything these days. People search for knowledge and Google shop.

With that said, I promote the Cool Pro Flush in these situations.

https://www.ackits.com/tools/flush-equi ... at/page/2/