1ST MAINT. TUNE-UP UNDER SERVICE AGREEMENT FOR 3 YR HT UNIT. CLEAN CHECK BURNERS AND BURNER OPERATION. LUBRICATE ALL NECESSARY MOVING PARTS, AND ADJUST BLOWER COMPONENTS. CHECK MANIFOLD GAS PRESSURE AND FOR PROPER VENTING. CHECK HEAT EXCHANGER, HIGH LIMIT CONTROL, FAN CONTROL, THERMOSTAT, AIRFLOW, AIR FILTER, ENERGY CONSUMPTION, AND ALL ELECTRICAL CONNECTIONS. EVERYTHING IS RUNNING GREAT.