Anticipating that I may convert my 85 300D back to R12 (had R134a, then Envirosafe ES12a, and currently R152a in it) , I am collecting /making tools needed to do the job successfully. This is a great opportunity for me to get hands on experience on AC work. I was curious about electronic leak detectors but do not want to spend a few hundred bucks or more on a name brand unit. When I saw this HF unit
Electronic Freon and Halogen Leak Detector on sale, comes to just under $60 with 20% off coupon, I gave it a try. Hey if it false alarms, I have 90 days to return it and get a full refund.
Here are 2 videos. The bottle was totally dry when I vented what was trapped in the high pressure hose of the manifold gauge set after taking a pressure reading of the R152a. First video is just opening the cap slightly. Second video is puncturing the bottle with an awl simulating a slow leak. As you can see, it was able to detect R152a with no false alarm. This HF 92514 detector works with refrigerants which contain chlorine and fluorine such as R134A, R12 and R22. R152a is Difluoroethane which contains Fluorine which this HF detector will detect. It is legal and cheap as a tracer gas (3 cans for $11 at Walmart), unlike R22. I have a 30 lb jug of R12 which I'll vent some into a bottle and repeat the test.
https://www.youtube.com/watch?v=lHcqFJw5txY
https://www.youtube.com/watch?v=9Wmj7sd7i34