Description : What should R-134 charged systems should be leak checked with?
Last Answer : Halogen sniffer or luminescent dye with a UV light. If you'vealready evacuated the system, and have a means to do this andevacuate it afterwards, I'll often take compressed nitrogen, put a250 psi positive charge on each side, and see what turns up. Thisis done after I know for sure there's a leak.