Regarding the ultrasonic leak detector, try to use it near an high voltage line and You will discover that We have ***** inside ,together with 440 volts... :-) This kind of technology need to be a bit improved before to become reliable for Us.... And regarding the electronics leak detectors, personally, I don't trust any of them, I tried various kind and brand and the only one that looks like to be effective are the Yokogawa, but as I said ,this is my personal opinion...
Evapcoil