My oil furnace and water heater both have a tiny LED status bulb that goes from green to red when they have ignition issues. I’d like to be alerted when that happens. Any thoughts?
If you are into DIY a $5 ESP8266 and ESPHome could monitor the voltage across each led to determine which was on. Issues with this:
- They may use back to back LEDs without a common anode or cathode, like this:
- The LEDs may be floating at mains voltage.
Both of these issues could be solved with a couple of optocouplers.
Or if you don’t mind blocking the visibility of the LED(s) you could cover it with an LDR or photodiode. If that does not have a spectral response capable of distinguishing between the two colours a simple red or green filter would help. This has the advantage of being totally non contact with the existing circuit.
I’ve built a couple of esp32 things - maybe I’ll end up using this:
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I have the same need, although I need just to recognize whether a certain led is on. or off.
My 20 years old heat pump has a led when the 8 kW resistor is used to heat the water and I would like to collect statistics based on this.
I do not have any power supply nearby, so I prefer a low power solution. ESPHome based solutions use always wifi according to my understanding.
I found this device, but it is Z-Wave, which would need another gateway. Anyone knowing 433MHz or Zigbee based solutions?
I have this to monitor the power consumption in the house using the led detection, but I could not see any ways to use that device for detecting whether a led is on or off.