Upon arrival found that unit 112 which covers right side conference room was not cooling. Checked inside unit and found that the drain line was clogged and the filter was dirty. Checked outdoor unit and found pressures a little low, spoke to Michael and wanted to add Freon and clear out the drain line. Added 3lbs of 410-A to system to set charge. Went to inside unit and cut drain line and blew out trap and line. Primped trap and watched system drain properly. System is now cooling at this time.