[jasonjayr]

Don't have a git repo or pictures up; but I've built:

1) a fridge door monitoring system. We have a fridge in our garage that doesn't see frequent traffic, and it does NOT have an alarm on the door if it's left open too long. an esp8266 Watches 2 reed switches and transmits the status to home assistant. I 3d-Printed a case for the MCU + 2 holders for the reed switches (for the freezer + fridge)

2) A passive LIDAR based sensor for watching our oil burner's tank's gauge. I have to finish this up into home assistant, but I've been collecting the position into a log file. I 3d-printed another cylinder that fits over the transparent gauge, and positions the sensor in just the right place so it can reflect over the opaque float inside the sensor. Even though it's external, this one I have to be careful so the main ESP8266 is a bit aways from the sensor + tank, and I should add more protection to the lines going to the sensor. Electronic devices near fuel can get ... spicey if you are not careful.

[pridkett]

I’ve done something similar with my fuel oil tank, except I’ve got an ultrasonic sensor threaded into my inspection port. It’s connected to a PoE powered ESP32. And now you’ve got me really concerned that even though I’ve got two compartments on the case (which itself is shoved inside a PVC pipe), I should probably do more to move the PoE powered ESP further away.

All that so I can be sure I have enough heat on really cold days or if the power goes out.

[briHass]

I wouldn't worry too much, diesel/fuel oil isn't like gasoline or other volatile flammable liquids that ignite easily from sparks. The burner 'gun' gets it to flame only by atomizing it with an intricate nozzle, lots of air, and 100 psi of pressure.