I just installed a new iris contact sensor. It is showing this:
Is there any way to get it to display the correct temperature?
My first recommendation is to turn on the heater.
Does it report open/closed correctly?
You can try to pop the battery out for a couple minutes and put it back in to see if that fixes it. I know that used to fix some of the temperature issues with the monoprice motion sensors.
I returned it for a replacement at my local lowes. The new one is working fine. 67 degrees Fahrenheit in my house now.
One I recently purchased alternated between -557 and -97. Open/Closed reported fine. Tried unpairing and repairing. Ended up taking back and getting another.