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