Successful Install of the Fridge and Freezer Temp Sensors


I had an earlier post requesting solutions regarding temperature sensors. Given some research and further consideration, I chose to go with the Fibaro FGBS-222 and 2 DS 18 B 20 temperature sensors. I ordered the 3 m length versions, as well as a 12 V power supply that came with the connecting adapter. I was very happy to see that indeed the single Fibaro was able to report two discrete temperature sensors. Apparently it can support up to six. I was concerned initially because the temperature sensors are connected in parallel. The Fibaro unit paired easily, and in the device set up menu I chose 2 DS 18 B 20 sensors and Hubitat created discrete devices that I was then able to place on the dashboard.

The only pitfall is that I was playing with very thin wires, about 22 to 24gauge, where wire stripping became an issue. I actually invested in a new wire stripper from the big-box store that supported up to 30gauge wires. I think altogether the setup came in at about $65-$70. What I now have is temperature monitoring that does not depend on batteries, and the actual transmitter is outside of the refrigerator. I chose to use electrical tape to secure this very delicate unit to the top of the units. I ran the probe wires through the gasket in the hinge side of the door and tape them inside to the wall. In the future, I will get plastic cups with lids that hold propylene glycol and insert the probe there. From what I came across, this provides more steady temp readings.

The dashboard icons report the temperature that I desired and I'm very happy. In the near future, I will play with various announcing mechanisms to report out of range temperature. I highly recommend this setup for anyone who wants to monitor refrigerators or freezers. My installation is somewhat ghetto, but it serves the purpose, and it works.

Thank you to all who contributed to my previous thread and it's great to be a part of this community.


You plan on adding door sensors to that fridge as well? I know that some users used contact sensors in the fridge for temperature and door sense capabilities.
From my own experience trying to do that, 3M doesn't adhere well to the cold plastic. Might work better if I used silicone instead.

Good suggestion. So far my white electrical tape is sticking well. I am really happy with the setup I made. No batteries. The z wave transmitter is outside the fridge and freezer. And that little z wave box can support 6 probes! Very cool. No more fridge/freeze surprises. I created an account with that twilio SMS service and have alert rules. This is very neat!

I'm really intrigued by that little Fibaro device, but I can't see how its powered. How are you powering yours?

Very simply, it is a 12 V, two amp DC power adapter.

tagging @JohnRob

after almost a year installed, I still didn't remove my 18650 battery (for charging purpose). And the door sensor works as expected (with some rule that warns me when the door is open after a 5 minutes delay)

frige monitoring

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I’m very aware of the advantages of no batteries, and I greatly respect that approach to monitoring refrigerator temperatures. It’s the ideal approach.

But if you just don’t have the time or inclination for that project, I just want to share the lazy approach some of us have taken. I installed Iris Motion Sensor v2 in my two refrigerators/freezers. This sensor also reports temperature. Using the Notifications app, I have a simple rule that notifies me when the temperature is above a certain level.

I’m about 18 months in, and I have yet to replace the batteries.

For good measure, I also added a contact sensor to the top of the refrigerator door, which because a top lip on the door, is basically hidden from view. This is on my double door refrigerator. When the door is left open for 5 minutes, I get a notification.

Not trying to derail this thread, but just in case someone does a search and comes across this thread, they’ll be aware of this less than ideal solution, but one that is super easy and works. However, if you have the time and inclination, the battery-less solution is superior.

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I just did this setup to monitor freezers. I have 5 probes. I copied your settings. I put one probe in so I could label them and all the probes read 68 degrees. Trying to figure out if I did something wrong.