SmartSense Temp/Humidity in refrigerator - wrong temperature


(Jason) #1

I have a SmartThings SmartSense Temp/Humidity sensor in my refrigerator. The fridge is set to 33 deg so I set an alert to notify me if it goes above 45 degrees. I would get alerts then immediately check in the app but it would always show ~33 deg. I changed the alert to 48 then 55 just to see if that would make a difference, it doesn’t. I then put it in the freezer which is well below any of those settings with same results and the app shows ~4 deg. History also shows humidity updates about every 10 min so it appears to be communicating. Temperature happens much less frequently but all temp entries show 3 or 4 deg for the freezer.

One more data point is the alerts are always around :30 on the hour - actual times over the last 18 hours:
11:31
14:30
17:30
18:30
22:30
23:35
00:30
01:30
05:29
10:29

I have deleted and readded the alert. Does anyone have suggestions to remedy?

Thanks, Jason


(Tim Slagle) #2

Hey Jason,

Definitely give our support team a shout. We probably need to dig into the logs to see if there is anything going on that we can see and resolve for you.

support@smartthings.com


(JJG) #3

A refrigerator should be close to a “Faraday cage” and thus anything inside it should be unable to communicate by radio frequencies with the outside world.
You should first check that issue.
If that is part of your problem, instead of using the SmartSense Temperature sensor, you could use instead a Fibaro FGK-101\US outside of the Fridge and connecting the optional DS18B20 temperature sensor with a long 3 leads (flat) cable going inside the fridge.


(Paolo) #4

For what it’s worth, I’ve used the Smartsense multi-sensor inside (2) brands of freezers/refrigerators (Whirlpool and FrigidAire) and they’ve reported the temps without fail for (6) months now.


(Jason) #5

Could not agree more yet humidity is transmitted regularly every 10 minutes, temp on the other hand is spotty. I don’t understand how one can be consistent and the other not. It does work fine outside the fridge, will try different places to see if behavior changes.

Thanks, Jason


(JJG) #6

I agree it is extremely curious the SmartSense Temperature/Humidity Sensor reports one value (humidity) and not the other (temperature).
On the other hand, that could be related to the way the Device Handler for that sensor has been written by SmartThings : the report frequencies or report thresholds which trigger both events may be different, and thus behave differently.
For instance, with a report period for temperature of 1 hour, if you have a OK probability for HF transmission of only 33%, on the average you would get an event every 3 hours. But the humidity report may be triggered differently.

Anyway, from what you say, if the SmartSense sensor works perfectly OUTSIDE the fridge, then you DO HAVE a HF transmission issue.
How far from your Hub is your fridge ?
May be the fridge is with enough holes in its “Faraday cage” so that it does transmit, most of the times, a signal, but the signal is weak enough that it has a high false transmission probability, thus this erratic behavior ?
If you have a ZigBee repeater on hand, try to put it very close to the fridge, on the straight line going from the fridge to the hub.
SmartThings support may have other suggestions, based on their knowledge of the way the Device Handler for that sensor is written.