So one of my good friends that i went to school with got called to a large tonnage air conditioner for i believe a hotel or something along those lines. He got called there because their "regular" company could not make it there for a few days. He walked into the mechanical room and found empty cylinders of r22 everyhwhere. He automatically starts thinking ok, there is definitely a leak somewhere and these "regular" guys cant find it, or don't bother looking for it. What he found next was the most unbelievable thing ever... He found a Water Valve for a water cooled condensor sensing the low side pressure of the system, when the system pressure dropped below set-point it opened the water valve which was hooked to a cylinder of R22!!! Whenever low side dropped it would just start charging itself, and whenever these other guys got called there they were just changing the cylinder!!!
True story, ubelievable!