Upon arrival, found 2 heat pump systems. 1 unit only runs heat. Found O wire getting 22v. Tested wires and found the o wire was damaged. Replaced it with a spare wire. Still no AC. found thermostat not wired properly. Fixed it. Still no AC. bypassed the thermostat with new wiring set up. Unit began to cool. Client had a spare thermostat. Installed new stat. Unit is operational upon departure. Client signed up on maintenance program.