Dispatched for furnace tune-up. The components that are tested during the tuneup are heat exchanger, flame sensor, igniter, blower wheel, inducer, temp split and combustion in the heat exchanger. When inspecting the heat exchanger it was showing signs of cracking in the rusted out areas of the seals. Also during the combustion analysis it was detecting air from the blower entering the chambers. This is indicated a crack that can potentially leak carbon monoxide into the living area. Also the blower is extremely dirty and would need a cleaning. Just having 1/8 of dust on the blower wheel fins increase the amp draw and reduce the amount of air across the heat exchanger. The system also need to have a gas shutoff and gas line repaired. Thank you for allowing us in your house to provide the perfect home service and for being a member of the perfect family service club from your LBA Lead Service tech Calvin. If I provided a positive or five star experience. I’d appreciate you sharing y