Contact Sensor for Refrigerator or Freezer Door?

I'm wondering if there is something we can do to slow down their rate of sensing. Its been interesting watching the temperature in my (brand new, damned expensive) Hitachi fridge/freezer combo dashing up and down all the time. I was expecting the temperature control to be much more advanced. With this constant changing temperature I'm wondering if the devices are being hyperactive?

Yeah I noticed mine gong up and down a few degrees pretty often. I'm also wondering if the battery level being reported is really that accurate. I took the battery that was showing to be 23% and put it into my ST presence fob. It shows a battery level of 90%. Who knows???

These device little batteries do not like the cold temperatures, the same situation happens to the contact sensor on my mailbox in the winter time, and this year I'm replacing it with a solar usb powered motion sensor instead. Haven't had any issues with batteries on my fridges/freezers since I went in the direction I posted above.

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What do you hook the DS18B820 temp sensor into?

A Fibaro FGK-101 Contact Sensor ....I have 4 of these 2 fridges/2 freezers.

I believe the Qubino's will do the same thing (roughly)

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In this video the blue screw terminals inside accepts the 3 wires from the DS18B820 YouTube

Awww, didn't see your original post. Can you use the magnet for open/close and use the temp sensor on the same sensor?

Yes I use it for door open/close status and notify me if the temp gets to high both

Hmmm. You got me thinking now. How did you route the temp sensor cable? And how does it come out of the freezer?

If you can find a sensor using a CR2 battery (about the size of an AA battery but half as tall) like the Iris V2 contact sensor you can go about 18 months between battery changes when used in a 0 degree freezer; that's about what I've averaged for the last 3 years. I also use one in the mailbox; I just replaced it this week (installed Nov. '17; it lasted through a couple of NY winters with temps as low as -13F).

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The fridges the contact sensor is double sided taped on the bottom on the vent with the magnet on the bottom of the door.....the DS18B820 comes out of the sensor and goes inside on the floor of the fridge coming up and hanging on one of the shelves with the door closing on in the cable

Freezers are about the same way, just mounted in other non noticeable areas.

Iris V2 was one of the 3 different sensors I tried in the freezer that went from 100% to 10% in 2 days.....that was actually originally the ONLY reason I bought that sensor because I read online claims saying that one worked. So YMMV.

The other 2 was a Smartthings Multisensor with a coincell battery (CR2477 I believe?) and the other was the Fibaro FGK-101 WITHOUT the DS18B1820 attached and itself in the freezer. All 3....2 zigbee and one zwave all batteries failed in 2 days

I was going to add that even with the beefier CR2 battery the reporting accuracy gives no clue as to its longevity. There really isn't a good way to give accurate battery readings in most of these sensors (I still have a couple of vibration sensors on ST on my washer & dryer; I've been getting nagged for weeks that they are at 1% yet still work OK). For the Iris in the freezer application, mine typically sat at less than 30% for over a year (and do drop rapidly, initially, as you noted). I guess the downside is that you have to have a scheme for proactively replacing it, since you can't get an adequate warning when it dies.

Ya I have to rely heavily on the battery % being "somewhat" accurate when it comes to the freezers with a couple grand worth of meat, I cannot risk losing. If the freezer gets above 25 degrees you would think someone is breaking in the house with all the notifications I have going off......so when the battery level gets below 40% on those sensors batteries in particular they get replaced, as I can't get notifications from dead sensors.

I bought a bunch of v1's. Ugly great big things I'm too embarrassed to fit to doors and windows. Now you've given me a good idea to see if they last longer in my fridge and freezer as temperature sensors! At least that will use up 2 of these monstrosities :slight_smile:

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LOL. Just what I did...

The Iris V2 can stand heat as well as cold; I put one in my attic last year and its hanging in there (it works as well at 119F as it does at ten below). I'd assume the V1 is just as good if it uses a decent battery.

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Cool, thanks Tony. Will give it a go!

@Tony
The Iris v2 Motion and Temperature Sensor (model 3326-L) worked for you in the freezer and the battery lasted 18 months?

The spec sheet for the Iris v2 (model 3326-L) Motion and Temperature Sensor states operating temperature is 0 to 40 Celsius. O Celsius equals 32 Fahrenheit.

Just want to make sure Iā€™m correctly understanding your experience.

Yes that's correct, in my freezer and outdoors, well outside of its specified operating parameters. It's definitely an off-label application and nothing I would expect the manufacturer to support.

It may have been my good luck (I use two in my refrigerator freezer and four others outdoors) but similar performance of this device has been reported by other owners in this form and others.