Upon arrival found that this kirklands has three RTU’s. Performed a three system maintenance. RTU 1 has some issues, one circuit has a bad compressor and one circuit flat on Freon along with one of the two fan motors disconnected and found it shorted to ground. With amount of repairs needed recommend replacing RTU 1 RTU 1 is not cooling. Found RTU 2 disconnect turned off, found no issues before turning power on. Turned power and tested heating and cooling. Found that both circuits were low on Freon and unit was freezing up, disconnected y1&y2, RTU 2 is not cooling. Recommend doing a leak search or replacing RTU2. RTU 3 which does the front found no issues. Need a total of 12-20x20x2. Changed filters.