Preventative maintenence inspection on Carrier high efficiency furnace running in great condition. AA21y air filter in dirty condition. Filter will need replaced soon. #35 humidifier pad in good condition, damper opened and water valve turned on for minimal amount. Clean flame sensor and check ignitor. Visual inspection of burners. Flush condensation trap and drain lines. Run test unit in heating mode. Temperature rise is within specs. Blower and inducer motors tested good. Pvc flue vents in good condition and no sign of leaks. 0PPM CO detected during testing. Humidifier tested during heating mode test. Dehumidifier is off for Winter. All systems are operating properly, efficiently and ready for Winter.