13 POINT MAINTENANCE TUNE-UP FOR A 3YR & 2YR HEATING UNIT. CLEAN AND CHECK BURNERS AND BURNER OPERATION. CHECK THERMOSTAT, AIR FILTER, AIRFLOW, HUMIDIFIER, FAN CONTROL, ENERGY CONSUMPTION, HEAT EXCHANGER, HIGH LIMIT CONTROL, AND ALL ELECTRICAL CONNECTIONS. CHECK MANIFOLD GAS PRESSURE AND PROPER VENTING. LUBRICATE ALL NECESSARY MOVING PARTS, AND ADJUST BLOWER COMPONENTS.