FIRST CLEAN AND CHECK 15YR HEATING UNIT UNDER SERVICE AGREEMENT. CLEAN AND CHECK BURNERS AND BURNER OPERATION. CHECK HEAT EXCHANGER, HIGH LIMIT CONTROL, THERMOSTAT, AIR FILTER, AIRFLOW, ENERGY CONSUMPTION, HUMIDIFIER, AND ALL ELECTRICAL CONNECTIONS. LUBRICATE ALL NECESSARY MOVING PARTS, AND ADJUST BLOWER COMPONENTS.