I just repaired my 5.5yo Robovac 11 with the same ‘roller stuck’ problem. The problem was not the roller brush or the gears. It was the roller motor itself.
There is a small gap of motor shaft visible between the motor bearing and the gear. This bit of exposed shaft collected a bunch of fibers. These fibers pulled the shaft out, misaligning it within the motor. This misalignment made the motor stiff to spin by hand, exactly as Paul Guilfoyle described. Once I removed the fibers, which was difficult to do, the shaft was easily pushed back into place and the motor spun very easily. There is, however, some “back and forth” play with the motor shaft that might cause the problem again in the future. I also added a small drop of WD-40 to each motor bearing to lubricate and protect from humidity. After reassembly, everything worked great. We’ll see how long it lasts before I have to do it again.
This, of course, is just one thing more to check among all the other things already mentioned.
Robovac 11 Rotating Brush fault
So the issue came back on my end. I checked the connector and it’s 100% snug so that’s not the issue. I’ll check the roller brush motor again for those famous fibers but I didn’t notice anything when I took it apart last time.
Honestly if the roller fiber thing isn’t the issue I think it will wind up at the eco-center recycling facility.