This weekend, I started setting up my first HA instance. My first and main goal is to monitor the fridge and deep freeze sitting in my garage. Kids of cost me two expensive clean outs already. I setup an aqara door sensor, which are magnetic switches. While they do work, getting placement exact is not great. I am having an issue finding a position to get reliable readings, and not being able to leave the door just lightly cracked.
My thought is like a pin switch or similar. Hopefully, not having to create one from an esp32, though not out of the question. Does this exist in a purchasable form, or am I stuck to wiring and 3d-printing?
Check out Aqara water leak detectors. They have two external contacts that when they are bridged change the sensor state to ON. You can run wires to those contacts.
Interesting idea.
Surely the best approach here is a temp sensor with a threshold at which to alarm? Then you’re actually monitoring the state of the appliance, not the state of the door.
While that is a solution and solves a big issue, especially like a power outage, a door sensor stops this problem long before that is an issue. My freezers and fridges are on the whole house generator, so power problems don’t effect them. A temp sensor is still a valid thing long term but does not solve the problem I am trying to solve.
I second this… it also has the advantage of alerting you if fuse pops / someone’s unplugged it / whatever reason.
There was a recent discussion about this very topic recently…
What if you made a pin switch in combination with the magnetic switch? Any magnet should work, the magnet from the magnet switch can be replaced with any magnet. Maybe you need a stronger one is all?
Open the door sensor, locate the reed switch, remove it and connect wires to its PCB pads. Although it should be pretty straightforward to measure the minimum distance required between the magnet and the sensor and install the magnet just a bit closer, so that any cracking of the door opens the switch. If you use a weaker magnet, the sensor will be more sensitive to the distance, so you will be able to detect smaller gaps.
Side note: if the door doesn’t close when there’s a small gap, the fridge might not be level or your door auto-closing mechanism might be worn out.
