FIRST MAINTENANCE CHECK-UP UNDER SERVICE AGREEMENT FOR 4 YR HT UNIT. CHECK MANIFOLD GAS PRESSURE AND FOR PROPER VENTING. CLEAN AND CHECK BURNERS AND BURNER OPERATION. LUBRICATE ALL NECESSARY MOVING PARTS AND ADJUST BLOWER COMPONENTS. CHECK THERMOSTAT, AIRFLOW, AIR FILTER, HEAT EXCHANGER, HIGH LIMIT CONTROL, FAN CONTROL, ENERGY CONSUMPTION, AND ALL ELECTRICAL CONNECTIONS. EVERYTHING IS RUNNING GREAT.