2ND CLEAN AND CHECK UNDER SERVICE AGREEMENT FOR A 6YR HEATING SYSTEM. CLEAN AND CHECK BURNERS AND BURNER OPERATION. CHECK THERMOSTAT, AIR FILTER, AIRFLOW, FAN CONTROL, ENERGY CONSUMPTION, HUMIDIFIER, AND ALL ELECTRICAL CONNECTIONS. LUBRICATE ALL NECESSARY MOVING PARTS, AND ADJUST BLOWER COMPONENTS. CHECK HEAT EXCHANGER, AND HIGH LIMIT CONTROL.