I have bought 2 StellaZ as a replacement for my Danfoss living and wanted to share my experiences.
First installation.
I thought it was a little fiddly. My radiator valves are very close to a wall, so i had a little problem getting the StellaZ onto the valve. Luckily on the second rad i had a little more room, so fitted the valve, then pushed the pin in for deinstallation. That way the white ring comes off, which i then put on the first rad and then managed to fit the StellaZ there too. I did not manage to get the white ring (which screws onto the valve) off with the StellaZ not mounted, which is definetely a minus.
Second inclusion.
I thought the manual was pretty rubbish. It tells you to press a button in the enclosure to get it into installation and/or inclusion mode. I finally found it, its a little blue button on the front. Once pressed StellaZ goes into installation/inclusion mode, and got picked up straight away by Vera as a thermostat. Given a few minutes to settle down and get all the information, it works fine, i can change the setpoint and it reports the room temperature as well as the new setpoint.
So far so good, lets see how it fares given a little time, see if i get communication failures like i did with the Danfoss, but so far, this is looking good (Not the StellaZ though… that is ugly)
I will report back here once they have been running for a while
That is exactly why i tried them. I just did not see the point having to take out the batteries every 2 to 3 days to get them to connect. The StellaZ’s are so far running without ANY problems whatsoever.
I have exactly the same thermostat. You managed it is programmed in the mode Direct Valve Control? Direct Control: BASIC SET 0xfe, THERMOSTAT MODE SET 0x1f
Already the second day trying to do it on Vera Lite
As far as i understand you cannot switch the different modes from Vera (due to lack of support for the raw zwave commands needed). but in default mode (comfort mode) it is possible to change the setpoint. I do not think you can do anything else with it at the moment, unless MCV change or add support for these commands. So at the moment i believe all you can do is change the setpoint and get temperature readings which you can use for example in PLEG. You also get the battery status.
Sounds as if Vera is stuck configuring the device ? If that is the case press the little blue button once quickly. That should wake up the thermostat end finish off the configuration. You might want to press configure node in the device settings, then wake up the thermostat
Got mine today. I have to say that I don’t find it that ugly, it blends nicely into the background Inclusing and installation was uneventful.
The valve reacts nicely to set point changes (which is what I was looking for, for certain rooms). I did find the reported temperature to be a bit on the high side (24 degrees when it’s more like 19-20; the heating’s off), so I may have to apply an offset (I already do this for my Danfoss TRVs, to account for the generally higher temperature in the vicinity of the radiator).
I’ll monitor battery usage over time; I’ve set the wake up interval to the lowest value of 4 minutes.
I’ll have to wait for winter to see how well it keeps the room at the right temperature. Often, the boiler will be running to heat other rooms, so it usually is the TRV doing all the regulating. The Danfoss did a pretty good job at that.
I’ve had this on test for a week or so now and so far it’s looking like a nice device.
To come back on a couple of points.
Currently you cannot change its ‘mode’ it will only work in comfort mode in VERA, this is because you need to send ‘raw’ Z-Wave commands to it and I don’t believe this is possible.
However, this does not mean that you cannot use it and change it’s setpoint from within VERA.
If you run a scene or PLEG scene, you can change its setpoint to what every value you like and this will control the radiators (as Mike mentioned). This guide shows the theory of how to do it in basic VERA scenes, but PLEG would be a better way to do it. http://www.vesternet.com/resources/application-notes/apnt-21. The guide uses a Secure thermostat, but it is the same idea.
I’ve had a scene running that uses the StellaZ temperature sensor as input to the scene and then based on the time of day the scene sets the device’s setpoint.
I need to direct management to the thermostat. This is in order to properly regulate the temperature. In 90% of users of the thermal head is not installed correctly (vertically, behind curtains, in-depth, etc.) and they do not work at room temperature, and the temperature radiators, temperature behind curtains, the temperature in the recess. To avoid this, I want to measure temperatures under an independent thermostat in the room and directly control the thermal head.
This is what i am trying to do, i use a seperate temperature device to regulate the setpoint of the thermostat via PLEG. That is the same as direct control as far as i understand ? I could be wrong though
Only I have a problem with the stem thermal head? When it is put forward to the maximum position, out of the guides and back are not enters on them (only occurs under load).
Inclusing and installation was uneventful.