How to digitally replace a potentiometer for continuous fan speed control

My ultimate goal is to integrate a fan, which uses a type of potentiometer to control the airflow, into Home Assistant so that I can regulate the fan speed with HA. I have this fan [LINK]. My question is, what options do I have to digitally replace the potentiometer? Digital potentiometer and ESP32? Problem is, that the potentiometer probably has high voltage inputs. The fan is for my growbox and I have everything integrated already from water to light and temperatur/humidity. The only thing missing is to regulate the fan speed as a function of the temp/humidity.

Depending on how far you need to turn the knob (only by 20 degrees or multiple turns), you could try a strong servo or a stepper motor. So keeping the original poti, but making it controllable mechanically.

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Hmm… I never thought about that. It’s only like a 3/4 turn. I have a 3D printer so it would be easy to print an adapter to a stepper motor. Also it would be cool to play around with a stepper motor for the first time.

How do you know it’s a potentiometer?
Are you sure it’s not PWM?

If it is PWM then you could get a smart dimmer and control it with that.
Like Sonoff, Shelly, Tuya.

Like @Lakini said, if it does 3/4 turn a 270 degree servo is the way to go.

Oh, please dont use servos to control things like this. There’s better waya that allow you to automate it and not lose the ability to manually turn the speed dial like you would with a servo awkwardly mounted to the dial.