Based on our findings today, it might be time to think about getting a brand new furnace. Today we came out for main level not heating 2006 Bryant 75k furnace with rheem 2016 ac 3 ton drive. Cycled equipment from thermostat found seized up draft inducer motor. Inspected heat exchanger with digital camera found crack @ 7 o clock tagged furnace unsafe to operate in heating mode due to potential carbon monoxide fumes. Flue piping is not up to current code due to single wall piping and gas line is not up to code due to flexible gas line tied into gas valve must be hard pipe and client has minimal flood protection and no emergency drain pan.