I performed a thorough furnace tune-up to ensure safe, efficient, and reliable operation. This included inspecting the heat exchanger for cracks and corrosion, verifying the operation of all safety controls, and checking the venting system for proper draft and obstruction-free flue path. I cleaned the burner assembly, tested the flame sensor, and inspected the igniter. I also balanced the blower wheel, checked electrical connections, and verified the airflow through the ducts. After completing the maintenance, I ran the furnace through a heating cycle to confirm smooth startup and stable operation. The system is now operating safely and within manufacturer specifications.