CLEAN AND CHECK 2YR HEATING SYSTEM. CHECK HEAT EXCHANGER AND HIGH LIMIT CONTROL. CHECK THERMOSTAT, AIR FILTER, AIRFLOW, FAN CONTROL, ENERGY CONSUMPTION, HUMIDIFIER, AND ALL ELECTRICAL CONNECTIONS. CLEAN AND CHECK BURNERS AND BURNER OPERATION. CHECK MANIFOLD GAS PRESSURE AND FOR PROPER VENTING. LUBRICATE ALL NECESSARY MOVING PARTS, AND ADJUST BLOWER COMPONENTS.