Performed maintenance on a three-zone A/C and heating system. Cleaned the condenser coils and evaporator coils in each zone to ensure optimal heat exchange. Checked and adjusted refrigerant levels as needed. Inspected and lubricated the blower motors and capacitors for each zone. Verified the accuracy of thermostats and ensured proper operation of zone dampers. For heating, cleaned the burner assemblies and checked the heat exchangers. Tested the system to ensure efficient and balanced comfort across all zones.