Today I performed maintenance on heating side of trane gas package unit. Upon start up I looked over heat exchanger with camera and found nothing concerning as far as cracks or rust go inside heat exchanger. I checked gas pressure and dropped it from 3.9 to 3.5 to ensure proper air/ fuel ratio for longevity of system. I checked over electrical and found some exposed low voltage wiring, took pics and taped it up to prevent any further exposure to elements, no wires where harmed. Checked blower wheel and fan bearings and both where tight. Cleaned out burner area and flame sense then started system up, inducer motor has rusted fan wheel causing some racket. Quoted price to repair issue. System still operates as is but is noisy and that motor is on its last leg. Blew out drain line to ensure flow when AC season comes back first thing. Sealed some spaces on flashing to unit. No other issues found. Will contact cst and explain situation and see if we can move forward replacing under motor.