Horstmann HRT4-ZW NaN

Finally got this to be recognizes by Veralite with UI5, but I can’t set the temperature. NaN is displayed in the temperature field. What could be wrong?

reinstalled it a couple of times and now no set temperature is displaying…

I just realized: there is no set temperature displayed until I turn the wheel on the HT Thermostat and then NaN is displayed …

Having problems with the same thermostat. I have two, and the one I added before upgrading firmware is still working fine. The one I added after upgrade, does not show temperature and is falling in and out of Vera…Also shows NaN.

I upgraded from UI4 on Vera 2 to UI5 on Veralite. The HRT stopped working already after the UI4>UI5 upgrade on the Vera 2 and I started out from scratch on the Veralite.

I set the Thermostat to 21 and then went into the Advanced Settings and set the Current Temperature also to 21. Then I could set the temperature in 1 degree increments in Vera Control, wait for the next wakeup and the Thermostat would follow.

Setting the temperature on the Thermostat was not picked up by Vera Control.

The ambient temperature is read accurately and shown in Vera Control.

The Pollsettings are 10800 and I cannot change this to anything else.

Apparently there is something amiss here, but I cannot figure out what …

So I have this working. The only drawback: set point changes on the thermostat show up in the adanances settings, but not in the vera widget. So when i set the temperature on the thermostat e.g. From 21 to 17, the widget will still show 21. When I change it in the widget from 21 to 20, the thermostat will change from 17 to 20.

I can change the temperature only in one degree increments. That means I have to wait for the wakeup time to pass and then do it again. Not very practical. Tried setting a scene, but that didn’t work at all.

Any suggestions for a work around?

I have two of these that work fine on UI5. Perhaps yours is getting set up incorrectly for some reason. I have attached grabs of the settings I use for comparison.

thank you so much for uploading your settings!!

i realize that i must be on a different release, as my UI looks different from yours …
i cannot change the poll settings in mine, which i think has something to do with the set point not read from the thermostat.

i am attaching my settings …

what release are you on?

i must be on UI7 and this seems to be whats wrong!

Yes - you are running UI7. This is reported to give problems with thermostats. I have not yet seen a solution posted but it may be worth a search. You could also try contacting Vera Support to see if they have a fix.

I don’t know how many hours I spent on this! I think I will try to return the Veralite and reinstall the Vera 2, which I replaced because it would go offline from time to time and I had to ask a neighbor to power cycle it.

I’m really getting tired of vera …

Or you could keep the Vera Lite but switch it onto UI5 - which supports the HRT4-ZW just fine. If you purchased it recently, you may need Vera Support to turn off the auto-update flag so that it doesn’t keep overwriting UI5 with UI7.

With 2 days left before I return to the US it is too risky to start a downgrade project. So I will live with it for now and I hope that they will fix this in a future release …

There is a bug in ui7 so just follow up this instructions and everything will be working ok:


To change poll setting just go to your device and change it inside Settings, not in advance.

That did it! THANKS :-*