Power mode Xiaomi heater s

[joselito.fb]

Hello ,
I have seen that you can set the heater to power mode so that you can decide how much power you want the heater to use, low, medium, max...
I have seen that this mode can be set by pressing (in the heater, not in the app) the temperature selector during 5 secs , but I don't see how to select the power level.
This mode is very useful at night because when used the heater does not switch on and off and does not produce any noise.
Does anyone know how to set the power level?
Thank you

 

[Homeye]

I guess this method is for the model without the lcd panel?
I have the one which can show the actual humidity and temperature, have an on/off, wifi, temp + and - buttons. Tried to press the + and - but no power mode for me.