I am having a problem locating a part for a duo therm model number 39025-501. The part number is 3106690005. I also need the impeller for this unit. The problem is that when I got there, the motor was missing and the customer told me that the "technician" removed the motor last summer and never returned. When the customer contacted him for the original motor he said that he had lost it. There isn't a schematic for this unit and there isn't any nomenclature to tell me what kind of replacement motor I need. PLEASE HELP!