I performed a fall HVAC tune-up to ensure the system was ready for cooler weather. I inspected the heat exchanger for cracks, cleaned the burners, and checked the blower motor for proper operation. I also replaced the air filter and tested the thermostat to ensure it was accurately controlling the temperature. The flame sensor was cleaned for optimal performance, and I verified the safety controls to ensure the system was operating safely. After running a final test, the furnace was fully prepped for fall and winter use.