Continuing the discussion from Do we have AC gauges?:
Do you mean stuff like this:
https://www.amazon.com/Interdynamics-ACP-102-Synthetic-Recharge-R-134a/dp/B007USCMJM
If so, what makes it inferior to other R134a refrigerant? I assumed it all met the same basic specs?
I have to say, be very careful of your sources of refrigerant. The Chinese have put R-40 into some R-134a canisters.
Here is an article about it. There is another article about it that I read recently stating that there was an influx of it to the US.
https://www.sae.org/works/upcomingmeetingResources.do?eventGenNum=13979
We ended up having some in some of our equipment that we found during a refrigerant analysis.
Sigh…figures. At least it is not laced with Fenatnyl :–(
So next question: how does one know what or where to buy? Does U.S. actually make any (thing!) of this under any sort of oversight?
Are you sure that’s not another shoe waiting to drop? 
Wow.
R-40 is considered the worst contaminant for R-134a. If R-40 is found in a system, it is considered unrepairable. There is no safe and approved solution for removing the refrigerant and neutralizing the aluminum compound that may have been formed.
Does anyone think 12 oz traditional can tap R134A is at meaningful risk of r40 laced product at Walmart, O’Reilly auto, or generally competent looking ‘zon listings?
I’m really not wanting to source 30 lb cylinders and scales just to try to avoid nasty contaminants.
Dollars to donuts Tim’s story involved bulk amounts/vessels/procedures so I’m not so sure I’d consider that to be a “better” path to avoidance…
Also, the report is dated November 2020 and refers to only one product/brand of concern (Cool Penguin F-12.). So it’s unclear if this was the only product found to be contaminated or if the timeframe had anything to do with opportunists and Covid.
But if O’Reilly’s and Autozone are continuing to sell the DIY products for so long, I’d have to expect they’d have good reason to not be concerned.
