The video (not mine!) explains the settings of a similar system I am using. For more info, go to http://openenergymonitor.org/emon/
Other sites where I publish live data: http://daturach.github.io/
Attic and external Temperature and Humidity situation plus external Pressure. Hosted ion a Raspberry PI. External sensor based on Arduino Nanao, 433 mhx TX, solar powered. Same data sent as IN3AQK call sign on APRS network
Raspberry BCM2711-CPU's temperature monitor. Data reading from the /sys/class/thermal_zone file. The RasPi pin GPIO4 connected an Dallas DS18b20 sensor. Field-2 present the room temperature. Channel update every two minutes.