Thermostat - safety function


I was thinking about this situation (LCD thermostat project):

If the heating is “ON” ( relay is switched ON ) and for any reason the power controller lost connection to the gateway (for example the raspberry Pi dies ) . The relay will stay on “forever” and so the heating.

Is there any way for power controller to automatically switch relay OFF if it lost connection to the gateway ?


An interesting idea, add a safety fuse, but in automation system for heating is used ON for fault state. It is better overheated than frosting the pipes.

this feature is useful. I had a thermostat with bistable relay and guess in which relay state the batteries died in the middle of night :slight_smile:

This would be easily solved by sending the relay pulse command. It exist for Relay Module but not for Power Module relay. We need to add that soon.

You send that you like to turn relay on for 10 minutes (600000 milliseconds) and if you send the same command after 4 minutes it starts counting that 10 minute again. So this will act as a fail-safe.


What do you think?

Hello Martin,

yes that looks like nice and elegant solution. It will even cover the situation when the lcd module´s batteries are flat but communication with gateway is not lost. My suggested solution would not work with this situation.
Will you please let me know when this feature will be added ?

thank you