pi4-fan-control

Run the fan when the temperature gets high

This module is designed to be installed globally and will compile to a single executable called fan which will probably be in /usr/local/bin.

The executable can be used to turn the fan on or off but is primarily designed to be run out of systemd to monitor the temperature and turn the fan on and off as necessary.

The program was written for the pi4 with the official case fan but should work on any fan with its control set to a single gpio pin.

It will work on Ubuntu on the pi4 where none of the official solutions seems to do the job. For wiring of the case fan, please see the page at raspberrypi.com.

Install

npm install -g pi4-fan-control

Usage

fan [options] [on|off]
    Run without [on|off], the fan program will turn the fan on and off
      depending on temperature
    fan on  - Turn the fan on and exit
    fan off - Turn the fan off and exit
    options:
       -h --help:       Show this message
       -v --version:    Display version and exit
       -x --max:        Temperature to turn the fan on    (default: 85)
       -n --min:        Temperature to turn the fan off   (default: 80)
       -p --pin         Pin to use for control            (default: 14)
       -y --delay       Polling frequency in seconds      (default:  2)
       -s --show        Display on/off messages on stdout (default: off)
       -d --debug       Turn on debugging mode            (default: off)

Running from systemd

You will need to create a service file: /etc/systemd/system/pi4-fan.service.

The contents should be something like:

[Unit]
Description=Fan controller for the pi4

[Service]
Type=notify
User=root
Group=root
ExecStart=/usr/local/bin/fan
TimeoutStartSec=60
NotifyAccess=all
Restart=always
KillSignal=SIGTERM
TimeoutStopSec=20
RestartSec=20

[Install]
WantedBy=multi-user.target

If you want a lower max/min temperature setting, add, for example --max 80 --min 72 to the ExecStart line.

If you want the fan on/off messages to be logged to the journal, add --show to the ExecStart line. They can then be seen with sudo journalctl -xe -u pi4-fan.

Having created this file, please run the following commands:

$ sudo systemctl daemon-reload
$ sudo systemctl enable pi4-fan.service
$ sudo systemctl start  pi4-fan.service
$ sudo systemctl status pi4-fan.service

This should show the service as running.

Node version issue

As of the time of writing, pkg-fetch does not support node version 17. Please either revert to node version 16 or run the javascript file directly from node, rather than the executable.

Changelog

v1.0.0: First public release
v1.0.2: Documentation fixes only
v1.1.0: Added the --show switch

Problems

Any issues or comments would be appreciated at Github.