Hi, I have Bryant 394GAD036075 carrier day & night furnace system. This unit was working fine as we start roofing work after that my furnace is not working any more. Problem deatils: Everything comes as per heating cycle, burner goes on and off , blower motor tries to blow but just making humming noise and shuts off when cycle is completed. Check fan control board no issues, replace high temp. limit switch but still problem is there. I tried AC cycle too same problem. I removed blower motor and power with external source, I think it works great for both low and high speed. But same blower motor do not work as a part of heating or cooling system.