CLEAN AND CHECK HT. CHECK THERMOSTAT, CHECK ALL ELECTRICAL CONNECTIONS, CHECK HUMIDIFIER, CHECK AIR FILTER, CHECK GAS PRESSURE ANF FOR PROPER VENTING, CHECK BURNERS AND BURNER OPERATION, CHECK HEAT EXCHANGER, CHECK HIGH LIMIT CONTROL.CHECK AIR FILTER. ADJUST BLOWER COMPONENTS, LUBRICATE ALL NECESSARY MOVING PARTS. EVERYTHING IS RUNNING GREAT. RENEWED SA.