13 POINT MAINTENANCE TUNE-UP UNDER SERVICE AGREEMENT FOR 20 YR HT UNIT. CLEAN AND CHECK BURNERS AND BURNER OPERATION. CHECK HEAT EXCHANGER, HIGH LIMIT CONTROL, FAN CONTROL, THERMOSTAT, AIR FILTER, ENERGY CONSUMPTION, AND ALL ELECTRICAL CONNECTIONS. CHECK MANIFOLD GAS PRESSURE AND FOR PROPER VENTING. LUBRICATE ALL NECESSARY MOVING PARTS, AND ADJUST BLOWER COMPONENTS. EVERYTHING IS OPERATING GOOD.