PoE HAT - noisy fan

[Juggler00]

I have the official Raspberry Pi PoE HAT and am running a fully-updated Raspbian. I am noticing that the fan on the PoE HAT is very noisy. It appears to spin up to 100% every 10-20s, run at 100% for ~60s then repeat.

I did some searching on the forums and have seen some comments on how to alter this behaviour. I’m looking for the actual, proper way to do this. Can anyone help?

[ShiftPlusOne]

Out of curiosity, what's the ambient temperature of the room and what's the pi doing when the fan kicks in, if anything?

Edit config.txt and add the following line:

Code: Select all

dtparam=poe_fan_temp0=80000,poe_fan_temp0_hyst=5000,poe_fan_temp1=82000,poe_fan_temp1_hyst=2000

That should change the behaviour so that the fan turns on at 80C, turns off when it comes back down to 75C. If the temperature reaches 82C it will go full blast until it drops back down to 80C. You can play with the values and adjust them so that they suit you.

https://github.com/raspberrypi/firmware ... ADME#L1649

It appears to spin up to 100% every 10-20s, run at 100% for ~60s then repeat.

It shouldn't go to 100% right away, but let's check if the instructions above help before diagnosing further.

[Imperf3kt]

I thought the fan could only be controlled between 60 and 70 degrees. Is it now possible to force it to any desired value?

[ShiftPlusOne]

The behaviour of the fan could always be defined by the user. The most recent change (a few months back) was to make the temperature and hysteresis values easily adjustable through config.txt, to cover most use cases without having to rebuild a device tree overlay.

[Juggler00]

The room is at 21ºC, so nothing extreme. I'm running ser2net on the Pi so that my instance of HomeAssistant sees the USB z-wave stick attached to the Pi as a local device. This does increase the network traffic, so I'm wondering if that could be causing the "freak out"?

I've made the changes to config.txt; so far so good. Thanks!!!

Out of curiosity, what's the ambient temperature of the room and what's the pi doing when the fan kicks in, if anything?

Edit config.txt and add the following line:

Code: Select all

dtparam=poe_fan_temp0=80000,poe_fan_temp0_hyst=5000,poe_fan_temp1=82000,poe_fan_temp1_hyst=2000

That should change the behaviour so that the fan turns on at 80C, turns off when it comes back down to 75C. If the temperature reaches 82C it will go full blast until it drops back down to 80C. You can play with the values and adjust them so that they suit you.

https://github.com/raspberrypi/firmware ... ADME#L1649

It appears to spin up to 100% every 10-20s, run at 100% for ~60s then repeat.

It shouldn't go to 100% right away, but let's check if the instructions above help before diagnosing further.

[80ov]

The behaviour of the fan could always be defined by the user. The most recent change (a few months back) was to make the temperature and hysteresis values easily adjustable through config.txt, to cover most use cases without having to rebuild a device tree overlay.

On what the kernel does it work? I have 4.14.9x. After adding a line

dtparam=poe_fan_temp0=80000,poe_fan_temp0_hyst=5000,poe_fan_temp1=82000,poe_fan_temp1_hyst=2000

in to /boot/config.txt - raspberry did not boot after reboot.

[ShiftPlusOne]

On what the kernel does it work? I have 4.14.9x. After adding a line

dtparam=poe_fan_temp0=80000,poe_fan_temp0_hyst=5000,poe_fan_temp1=82000,poe_fan_temp1_hyst=2000

in to /boot/config.txt - raspberry did not boot after reboot.

Should work on all relatively recent kernels.

I've just tested it with rpi-update a08ece3 (4.14.98) and it seems to work.

Unrelated to this, but I've just noticed that config.txt dtparam lines seem to have a character limit. poe_fan_temp1_hyst=2000 is cut off, so you may wish to split it into two lines:

Code: Select all

dtparam=poe_fan_temp0=80000,poe_fan_temp0_hyst=5000
dtparam=poe_fan_temp1=82000,poe_fan_temp1_hyst=2000

[80ov]

On what the kernel does it work? I have 4.14.9x. After adding a line

dtparam=poe_fan_temp0=80000,poe_fan_temp0_hyst=5000,poe_fan_temp1=82000,poe_fan_temp1_hyst=2000

in to /boot/config.txt - raspberry did not boot after reboot.

Should work on all relatively recent kernels.

I've just tested it with rpi-update a08ece3 (4.14.98) and it seems to work.

Unrelated to this, but I've just noticed that config.txt dtparam lines seem to have a character limit. poe_fan_temp1_hyst=2000 is cut off, so you may wish to split it into two lines:

Code: Select all

dtparam=poe_fan_temp0=80000,poe_fan_temp0_hyst=5000
dtparam=poe_fan_temp1=82000,poe_fan_temp1_hyst=2000

Great, it worked!
Спасибо!

[ShiftPlusOne]

Great, it worked!
Спасибо!

Glad to hear it.

Незачто!