After half a day and trying everything I know, I finally admitted defeat and declared this unit unrepairable and sentenced her to death! I've had to recharge this unit 3 times this summer so I finally pulled it out of service to do a tear down in the shop. Leak detector found an evap leak with condensate pan still attached ( refrigerant pooling in pan) but once evap was out, I could not find it electronically. Nitro up to 235 psi with bubble soap and no luck. Finally, I submerged it in a garbage can of water but still no bubbles! Copper was very green so I'm attributing it to "green death". Wondering if anyone else has had impossible leaks to find?