CAME OUT TO SERVICE HEATING UNIT. CHECK THERMOSTAT, AIR FILTER, HEATING EXCHANGER, HIGH LIMIT CONTROL, HUMIDIFIER, ENERGY CONSUMPTION, GAS PRESSURE, AND ALL ELECTRICAL CONNECTIONS. CLEAN AND CHECK BURNERS AND BURNER OPERATION. LUBRICATE ALL NECESSARY MOVING PARTS, AND ADJUST BLOWER COMPONENTS. REPLACED VENT PIPE. EVERYTHING IS RUNNING GREAT.