Can not change fan speed

[hhc-skylar]

Hi @nordeep , thanks for the tutorial, to make sure the wiring match your schema, I use all the same modules and config as your project, but I can't change the speed in home assistant, just power on/off the fan.

First time I thought it might be something wrong with the fan (Delta 12V 3750RPM) so I tried Noctua A12*25 but still no luck. I had also tried different IRF520, 4-channel Logic Level Converter and Wemos D1 mini but no success.

Since it seems to have no difference when I changed the hardwares, could it be something wrong with ESPHome version ? The Latest one is ESPHome 2022.9.4.

Really appreciate for any help, thanks!

[nordeep]

I think first of all you need to doublecheck your schema of connections. Second - check wemos pins are assigned correct. And third - you can use multimeter tester and check V between FAN PWM and GND.

[hhc-skylar]

Hi, thanks for the help ! I have check the schema several times, but I haven't measure FAN PWM <-> GND, will check it and report back.

What I have check is HV<->GND and LV<->GND and make sure they are 5V and 3.3V. I have also switched pins setting between D6/D7 few times with no luck.

I think the problem might be either config or 4-channel Logic Level Converter since I can turn on/off successfully.

BTW how many Voltage should I get between FAN PWM and GND if the schema run correctly?

[nordeep]

PWM - GND you should see about 5V then you set 100% fan speed, and a little less then you limit speed to 1-2%. But it's PWM signal from wemos, maybe tester it's not best way to test, more accurate it's use oscilloscope. Anyway you should see changes on tester.

[hhc-skylar]

Hi @nordeep , sorry for the late reply, had a busy weekend. So I tried 4 fans and check their Voltage between PWM <-> GND, when set 100% speed, I got 3.3x V on PWM<->GND (tested on PWM pins of fans), and 1.6x~1.7x V when set to 2%~5%. Turn out that Logic Level Converter and ESPHome do work.

What surprising me is that one of the fan CAN change speed ! Please see the following details :

1. Delta 12V 3750RPM (FFB1212SH) 14.8W
   Failed. I have tried 25000, 30000, 35000, 10000 Hz and all failed.

2. Noctua NF-A12x25 2000RPM 1.68W Failed, only tried with 25000 Hz cause this fan is popular and all tutorials I found use this frequency.

3. MONTECH P120 1500RPM 19.2W Failed. Tried with 25000 and 20000Hz.

4. Cooler Master SickleFlow 120 1800RPM 1.8W Succeed ! Tried with 25000. Totally have no idea why this one can work.

But I got another problem, actually all fans can not operate stable even through the fan power supply is 48W(12v), for some reason the ESP8266 will lose power and died, and I have to unplug/plug the adapter of ESP8266 (Tried with two adapters 10W and 65W) to make it alive again.

So, besides the ESP8266 died problem, what should I tried next ? Should I change Logic Level Converter cause I suppose to get 5V when speed set to 100%, right?