in-wall bathroom heater, supposedly controlled by knob, doesn't always turn off. [View all]

An electric heater built into the wall. Turn the knob, it comes on. Try to turn it off by turning the knob, doesn't always happen.
Further, sometimes it just comes on by itself, with no one having touched the knob. It has a mind of its own.
Sometimes, it seems that I have to control it by turning off or on the breaker switch for it, which is out in the laundry room.

It's kind of a nuisance, could be a danger if I forget to flip the breaker.

Yes, I can solve this by never using it and using a plug-in little heater to warm the bathroom and never, ever having possibility of using the in-wall heater (because the breaker would disallow).

Just wondering what a fire department inspector would think of such a heater. (Rented apartment, landlords not great on maintenance.)