Yes, most vacuum cleaners have thermal cut-off switches mounted on the field of the motor itself. This is to prevent a fire should the user run it while it is clogged or when the filters need cleaning. If the vac switches back on after about 30 minutes, (the time it takes the motor to cool back down) that is a sure sign that there is a blockage somewhere or that the filters need cleaning or replacing.
www.bobsroswellvacuum.com, September 2008
