When I put my fan heater at the first hot scale the fan doesn't turn

@oldturkey03, My initial thought is that it probably doesn't use PWM for the fan speed. With only two or three different speeds needed, it's going to be cheaper to use a hardwired switch to change the speed rather than the electronics needed to generate a variable PWM signal. It seems to me that electrically-oriented designs (as opposed to electronically-oriented) like low end heaters tend to keep electronic components to a minimum.

It would be worthwhile to open up the heater and check the switch. I see two possibilities here; either the switch isn't directing power to the fan on the low speed, or the fan has the speeds built in and the low speed isn't working.

Vagelis, it would be useful if you could open up the heater and post pictures of the switches and the wiring that's connected to them. Also, a little clearer photo of the exterior controls would be appreciated.