Customer was concerned about RTU #3 not coming on and cooling. Got on roof and began to diagnose the system. Refrigerant circulating pump would come on, but not the air movement system. Voltage distribution system for air movement system not receiving 24 volts to pull in and distribute voltage. Traced issue back to the air movement system relay. Relay was faulted. Replaced relay and air movement system came on with the refrigerant circulating pump. Checked pressures in cool and found that the refrigerant pressure control system was not operating as it should giving us faulty pressures. System is cooling, but not to manufactures specifications. Informed customer of our findings, and will be getting with supply house on Monday to check availability and price of a new refrigerant pressure control system. Heat transfer media coil needs to be chemically cleaned as well as the drain pan underneath. Will update customer next week on a repair time. System cooling to the best of its ability at