I’ve been playing with PWM fan control, and general ‘PWM’ vs ‘LED Dimming’ is a bit confusing to me in Tasmota. I guess the easiest way is to just treat it as LED control, but I have been using the PWM command via MQTT which works fine.
A couple of additions:
I used Tasmota counters in another fan control project to get the fan RPM feedback, it works fine. Count for one minute and reset using rules (using teleperiod). Useful for critical installs to ensure the fan hasn’t failed. I’ve put some notes here (It also has thermostat control via rules with hysteresis values)
Tasmota out of the box will PWM control at 4kHz frequency max. The cheap PC fan I was testing with was a bit buzzy at that low freq, so I switched to esphome and went to 25kHz. Tasmota can do that with a simple recompile, but it might possibly affect other processes if there was a lot of other stuff going on. My fan control stalled the cheap fan at anything below about 60%, so speed feedback would be useful (I haven’t written this project up yet)
Just few more remarks:
The proposed template resulted in a controllable fan, but only the region of 90-100% of tasmota slider was effective.
Setting the Tasmota option
LedTable 0
helped a lot to extend the PWM region to around 50-100% of the fan power. And I believe increased the maximum power too, but that’s just a feeling.
And last one - in case the copy pasting of above template does not work for you (as it didn’t for me), it’s just the quotation marks that were somehow formated by the HA forum text editor. The values themselves are correct.
It was really painful as I was not receiving any error, the device just rebooted to its factory defaults after any attempting to use the “wrong” template. Changing the template from console gave a hint on what is going on…
