13 POINT CHECK-UP FOR 8YR HEATING SYSTEM. CLEAN AND CHECK BURNERS AND BURNER OPERATION. CHECK THERMOSTAT, AIR FILTER, HEAT EXCHANGER, HIGH LIMIT CONTROL, ENERGY CONSUMPTION, FAN CONTROL, GAS PRESSURE, HUMIDIFIER, AND ALL ELECTRICAL CONNECTIONS. LUBRICATE ALL NECESSARY MOVING PARTS, AND ADJUST BLOWER COMPONENTS.