I have a number of Zigbee door/window sensors and they work well on doors and windows but not on my fridge. I suspect the problem is the steel in the fridge. The sensor says the door is shut, even when it’ open.
Are there door sensors available that don’t have this problem?
Can’t you just add a router close to the fridge? Like a smart plug.
That might give it better reception
Already has one less than 2 meters away and in direct line of sight. The problem is the steel interfering with the sensor, not the transmitter. There’s a green LED in the device and it doesn’t flash when you open or close the fridge door.
Have you mounted it on the inside?
Try using a piece of plastic (maybe 3mm) as a spacer between the freezer and the sensor. Or place the sensor “upside down”, meaning that you will use the opposite side of the sensor that is normally used for fixing.
Can you post a pic of the placement?
I’ve taken it off and used it for another door now but the fridge is a standard fridge with a 15 mm gap for the magnetic seal. I placed the magnet on the outside vertical edge of the door and tried positioning the sensor in two different places: (1) on the edge of the fridge casing, which left a gap between the sensor and the magnet, and (2) offset so that it overlapped the seal and made contact with the sensor.
The device worked fine when not on the fridge. The sensing range was maybe 20mm so I was expecting it to work with a 15 mm gap. The problem though is that it is triggering even without the magnet so I’m assuming the steel case of the fridge has become magnetized. I’m looking for an alternative type of sensor. Maybe something with a microswitch or optical sensor.
Could a light sensor inside the fridge be an option?
No…
First because it would require a hole in the fridge to pass a power cable in.
Then also because the signal will have a hard time to get out.
If you are thinking of a battery powered device then that is a bad option too since batteries and cold climate does not work well.
I use aqara door switches on my fridge and freezer. They are on the outside on the top and bottom of the doors so not really visible
I also have a battery temp sensor inside the fridge and it has worked fine for years, battery lasts a year or so
I tried a spacer but it’s a very confined space.
I tried a different sensor (different design) and it worked ok so problem solved.
So the problem turned out to be the type of sensor I was using. I tried a different type and it worked no problem.
I couldn’t find any model numbers but there are both the type that take AAA batteries. The one that caused problems was rectangular and had a button in the battery compartment to put it in pairing mode. The one that worked is more rounded and the pairing button is recessed so you have to use the paperclip tool thing they give you.