the "smart outlets." My original concern was based on what I thought was
a
thermal overload kickout, but when I sealed up the unit I left plenty of
room for airflow and even put in a small fan to make sure nothing
overheated. I realize now I ran those tests during an average vacuuming
session that didn't include the occasional serious clog, so I will have to
see what happens when I deliberately block the hose and monitoring the
motor
temperature.

It is very possible that the power unit uses the filtered air from the
vacuum as cooling.