Incomplete 2 System worked on US Carrier HP Split System. HO stated system was not heating or cooling properly in different occations. First thing I found was the yellow wire at condenser unit was not making full contact, the wires inside wire nut were connected right, wire nut was loose. Thats why when I was removing electrical panel cover I could hear contactor pulling in and out . Repaired wire. Also Found Piston for heating at the condenser stopped up. Piston and filter dryer will need to be replaced. Can use filter dryer from truck stock. Old Filter dryer is located Outside the AH unit. Talked to HO about the situation.