Upon arrival the system had kicked off on high pressure. After finally getting roof access from maintenance i went to units. All 3 units were running. I went back down stairs to figure out which unit it was that had problems. The lady told me the wrong unit and I chevked it out and was fine. I went back had her shut the other two units off. Then I put it in charging mode. It called for a 8 subcooling. I had no superheated. I recovered refrigerant slowly until I hit target subcooling. I did not want it to take too much out and then have low pressure lockout. It is cooling at this time.