MAINT. TUNE-UP FOR 11YR HEATING SYSTEM. CHECK THERMOSTAT, HAD TO REPLACE UNDER WARRANTY. CLEAN AND CHECK BURNERS AND BURNER OPERATION. LUBRICATE ALL NECESSARY MOVING PARTS, AND ADJUST BLOWER COMPONENTS. CHECK AIR FILTER, HEAT EXCHANGER, HIGH LIMIT CONTROL, FAN CONTROL, ENERGY CONSUMPTION, GAS PRESSURE, HUMIDIFIER, AND ALL ELECTRICAL CONNECTIONS.