Performed a preferred customer furnace cleaning. Cleaned the burners and the flame sensor. Checked the furnace heat exchanger. Wiped down the inside of the furnace. Checked the electrical. Cycled the furnace. Performed a furnace combustion test. No issues with the furnace at this time. Replaced both the hepa filters. Cleaned the air to air filters. Checked the humidifier pad. The humidifier pad looks ok.