Performed heating maintenance, replaced air filter. Cleaned burners and flame sensor, inspected heat exchanger. Blew out condensate trap and drain. Serviced humidifier, cleaned and replaced water panel. Started humidifier, checked operation and set humidistat to 35%. Checked voltage, amperage and electrical connections, measured capacitor values. Started gas furnace, tested limit and safety switches. Performed combustion test. Checked operation and temperature rise.