Temperature Sensor in a Freezer

Does anyone use a temperature sensor in a freezer?
I'd like to check that the door hasn't been left open, or that the power is still on.

Is anyone using the Aqara temp/humidity sensor?
Any other recommendations?

I am using one of the PEQ moisture sensor in my freezer. Been working great for awhile now.

Do you have a metal door on the freezer?
Stand up or chest?
Battery still ok on that sensor?

It's a Viking built-in that is stainless. I actually have one in the freezer and one in the fridge. Both are working great and battery life is great so far also. One thing to note is that my hub is sitting above my kitchen cabinets and is near the freezer.

This is one of those applications where Wireless Tags are superb. I think there's a community integration for them now.


I use a contact sensor on the door, and Message Central tells me if it’s left open for more than 5 mins


This is what's I am using to tell me if the door has been opened for too long. I use the moisture sensor to monitor the defrost cycle.

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I use Fibaro's FGK-101 Contact sensors on the outside of the door with an attached DS18B820 Temp probe going inside of the Freezer. With the sensor staying outside the batteries last much longer.

However those FGK-101's are getting harder to come across lately, but I think Aeotec has a contact sensor now that is set up for an external probe.

I also have RM rules that notify if the temp gets above 25 degrees


Yes. Search the forums. I've used an Aqara in my freezer for around 4 months. It works fine despite showing negative battery.

So, what do I make of the fact that the Aqara sensor that I put in my freezer stopped reporting 4 hours ago?

That it ain’t gonna work for you !

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This project is on my short list. Once I get my wifi arduinos (Friday is Prime day!) I will be setting this up using a 10k thermister. I will share my code once I confirm it is working!

I have Iris Motion/Temperature 3326-L (v2) sensors in both the refrigerator and freezer. You can buy these sensors on eBay. A lot of 10 is $56. They are great motion and temperature sensors.

I receive a mobile notification if the temperature goes above a certain value. Working great so far. Still on original batteries for about the last 4 or 5 months.

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I had an Aqara in my freezer. It would stop working after a few hours also. It would start working again after it thawed out.

Here’s an option. Not Zigbee, but will get the job done.

I had one of these in SmartThings, but can’t seem to get it to work in Hubitat. Even when pairing next to the hub. What kind of driver are you using for it?

The stock Fibaro Door/Window Sensor 2 driver. Some people had the same problems with these, furthest we could figure out is theirs maybe were older firmware version. I have 8 of them all working fine.


The Hue motion sensor seems to be working out alright for me.


If you can find the original SmartThings V1 multi sensor these things are amazing. They take 2 AAAA batteries. The one in my freezer is now at 2.4 years on the same batteries. If you watch ebay they occasionally come up.

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I would agree the hue motion sensors do read that low as last month my outside temp got to -17 and it registered. Long term at those low temps I cannot confirm. Before I got these Fibaros I used a Iris v2 contact sensor it read that low, but the batteries would only last for about 2 days, So I went with the Fibaro's so I could use an external temp probe with it.