HoneyWell TH8320ZW always set temperature back to 85F



Last week I was browsing Lowes website and found TH8320ZW for $20. I got one right way (price is now back to $160).
Installation and pairing was as easy as it could be, around 15 minutes.

Everything appears to be working fine. When I set the temperature using the sliders (ST app), the thermostat responds near real time.

The problem:
I had it set on cool mode and hold on 74 degrees. From time to time I look at the app and it will tell me the temperature is set hold on 85 degrees instead (it switches automagically). At first I though it was a glitch on the UI so I went back to the thermostat it was actually showing 85.

This is bad because it means the AC will only turn on if the house temperature goes over 85.
Any thoughts?

(Jason) #2

I would do a Zwave exclude, then Re-include it to the system to see if that solves it.

If that doesn’t work, I suggest sending an email to since it’s on the compatibility list so they can look at the logs to see what’s going on.

(Ran) #3

I have this Thermostat. Before I did the install, I did a factory reset and just made sure I set up the Thermostat first. Then I did the pairing and all works as it should. I have not experience the problem that you are currently having.


I didn’t email support yet (even though it was a good suggestion) because I found something:

When it happened again I went to the thermostat and noticed it was running on a schedule.
Since I never touched the schedule when I programmed the thermostat it had this crazy defaults of high temperature such as 85, 82 and so on.

I took some time to program it according to my lifestyle and I will give it a few days and see how it goes.