Get notified when I don t receive mqtt messages anymore

[ukmoose]

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How can I get feedback from MQTT

Hi, I'm creating my first project. I want to control the start of my boiler. The system is very simple, an ESP32 reads the temperature and sends it once a minute to mosquito on a raspberry, node-red reads the temperature and commands the boiler. I realized that there might be a problem. If the boiler is on and the ESP32 board no longer sends the temperature, the boiler will never turn off. How can I tell with node-red if the sensor is still working? Thank you