They are all problematic. Environmental concerns, path to leak etc. Better off to look at any fittings charged and then chase the line down visually looking for chafing. They make a uv/die now that is pretty awesome in other scenarios. I don't see why it wouldn't be available in automotive uses by now. Keep us posted or i can look later.
Tracerline HBFTPOPUV17 Complete A/C & Fluid Dye UV Leak Detection Kit Couldn't help myself, had to look. Lots of results, Napa, Walmart, advance etc. No clue who National Tool Warehouse is or if tracerline is legit. I've personally used product like this purchased at an HVAC supply distributor (Johnstone supply) under license. The "sniffers" are just problematic. Product View Looks similiar to tracerline, lol.
Hello Mr Bob. I have been doing truck A/C work for a while. Really liked the one for R12 ( still have it ) but it would not work for R134A. The new units were stupid expensive then. Started using soapy water and dye. Have a caulking gun and tube from Snap On and it costs about $3 a shot. Yes it has glasses and a black light I have almost never used. I put dye in everything I charge. It catches most leaks without classes. I am sure the auto parts folks have something in a can that will work. For hard to find leaks I brazed old fitting ends closed so I could block off and pressure firewall forward or firewall back sections and watch for leaks. Work it down from there. It can take days and then always question my hose connections. Bought a Robin Air tester along the way. It is a very good tool but seldom use it. Always take the batteries out of it after use as it could be a long time before using it after learning other ways.