I've built an esp8266 based web thermostat to control my heating system. Everything seems to be working fine for the moment :)
What I want to accomplish is "sniff" or intercept the boiler´s status from the front panel's status LEDs, to see if this heater is actually turned on, on a MQTT Dashboard.
A very nasty way would be to connect some wires from the boiler's LEDs to some GPIO pins. But I'm not quite sure about that approach. I believe I would have to use some type of buffer, optoisolator, etc. (I could also place a LDR, o phototransistor in from of the boiler's LED, but I dont want to physically block the visual feedback)
How could I accomplish this? Any ideas?
Appreciate your help, Cheers! Marc
PD: This exact same question has been asked in the Arduino Forum almost a month ago, but haven´t received any replies yet. Sorry for the double post.