Hello
stonefree wrote: The fan has a motor probably with a tapping winding (3 fan speeds)
Did a colleague see the connection up close?
Sample here
stonefree wrote: The engine works only at the highest speed.
Is it connected to the power grid directly or via a regulator?
Examples of regulators for the Volcano heater VRMini VR1 VR2 models are below
I also attach other connection diagrams of the motors in the Volcando VRMini VR1 VR2 VR3 VRD heater.
stonefree wrote: I am looking for the possibility of rewinding this engine
It is not always worth it because copper (winding) is not cheap and e.g. a 2.2kW motor override is not worth doing it yourself.
However, here is a small engine around 0.5kW so it should not be expensive.
It may be worth contacting the distributor of this heater or an authorized service center to buy the engine itself, assuming, of course, that it is damaged.