I recently bought a refurbished powerbot r7070 and the left wheel stopped working. Everything was great for about a week before this issue occurred. I was hoping it was a minor issue but when i opened it up i couldn't see any jam or other visible issues. I am assuming it is the motor for that wheel. I called samsung and they dont sell parts for this model anymore.... So i am not sure what to do. I love the vaccum and i can get a refund for it but i got it at a once in a lifetime deal and would have to pay hundreds more for the same model =/