Maintain the temperature in a proofing box ("Gärbox" in german) using a raspberry pi and bit of hardware.

A daemon script gb-daemon.py monitors the temperature and activates or deactivates the heat source, to keep the temperature in the box within the configured temperature range. The heating is active, as long as the temperature in the box is below maxtemp. When the temperature in the box reaches maxtemp, the heating is switched off, until mintemp is reached again. The default settings are configures in /etc/gaerbox.conf. The daemon is started by systemd during boot.

The client script gb-client.py is used to query the current temperature of the box and to modify the minimum and maximum temperature in the box and other settings. The client must run locally on the same system as the daemon. Therefore, ssh access to the raspberry pi is needed.

The following commands are supported by gb-client.py

$ gb-client.py --help
usage: gbc [-h] [-mintemp MINTEMP] [-maxtemp MAXTEMP] [-status] [-stop]
           [-start] [-heat {on,off}] [-poweroff]

gaerbox client: allows to send commands to the gaerbox daemon, e.g. change the
minimum temperature or stop the daemon

optional arguments:
  -h, --help        show this help message and exit
  -mintemp MINTEMP  Set minimum temperature
  -maxtemp MAXTEMP  Set maximum temperature
  -status           Query some status information from the daemon
  -stop             Stop the daemon
  -start            Start the daemon
  -heat {on,off}    Switch heating on or off
  -poweroff         Shutdown the system

• raspberry pi
• a well isolated box
• a heat source, e.g. a heating mat for terrarium
• a temperature sensor (I used the DS18B20)
• a relay

so far a quick&dirty Makefile exist, which allows to install and deinstall gaerbox on Raspbian GNU/Linux 10 (buster).

todo...

• control the daemon using some kind of web application...