Questions about Stelpro STZW402+ Z-wave Thermostat

I just got a Stelpro STZW402+ Z-wave baseboard thermostat and installed it, but there are a couple odd things that I wonder if anyone can help with.

  1. Alexa does not seem to find it. I've enabled it in the Hubitat Alexa Skill app (as well as a Zigbee plug that I added at the same time). Alexa reported immediately that it understood the Zigbee plug, but not the thermostat. Then I told it to scan for new devices. nope.

  2. I'm using the driver supplied at the bottom. I could have sworn that I had earlier seen a different driver in github which was claimed to avoid logging the cycling on and off and was somewhat newer. But I can't find it.

So is there a better driver than this and should Alexa work with this device?

Thanks, and below this is the link.


For question 1: From what I understand, the Alexa Hubitat skill must let thermostat data be accessed and hubitat does not allow this for the moment, there has been a few requests for this to be implemented but still no go in the last update.

Oh yuk! I hope that the Maker app can at least make it turn on and off! That's really all I want to do is to turn off the heat when I leave the room!

I haven't tried this, but you might be able to create a virtual button and then create a RM rule to do what you need to do, I know I have a virtual button used to set my thermostat to hold wich is set to 10 degrees C in the thermostat app. When I leave the house I can just to the dashboard where my virtual button is and switch it to on for hold and everything goes down. Most likely you could add this virtual button to alexa and tell her to turn on "thermostat hold" or whatever you want to name it.

Worth a try I guess. Let me know if this works, I might just do the same (Hub is not at my main house so I can't test this until sunday when we go down to our weekend home).

Thanks. This particular thermo has two setpoints (normal and environmental or some such). The driver has a way to switch between them. That might be what the button activates. I'll give it a try. Good idea!

Ok, it works. Thanks again for the idea! One problem was that was unable to control the Eco vs Regular setting I was thinking about. I just had the virtual switch change the heat setpoint. And indeed, the virtual switch is visible to Alexa.

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Great, happy it works and I might try this and use Alexa to set it back when we leave.

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I'm not sure what I did in the process of setting up this virtual button etc, but I got the thermostat into a very weird mode such that it appears to heat to point that is maybe 4 or 5 degrees ABOVE the setpoint. I reset the thermostat to factory settings and it is ok.

I actually suspect that it was not so much the virtual button setup but rather some of the other setting on the thermometer device page, many of which seem to have no effect at all (but perhaps really did). If anyone has seen this behavior, I'd love to know if you have figured it out.

Would be nice if we could get a baked in driver for this T-stat. It doesn't seem like a very complicated one and they are one of the few making zwave baseboard controllers.

Just for anyone concerned about this last post of mine; This has never happened again. The t-stat has some odd-ish behavior (it is not very consistent in how much power it gives the radiator at a given temperature relative to the setpoint), it has never gotten totally screwed up like I mentioned here. I'm generally happy with it. But see my next post.

Ok, as I said a minute ago I have this running and it is working pretty well. I have one thing I would like and maybe someone has some ideas.

First let me say that I am a programmer, but that I don't really feel the desire to learn the driver language and write drivers. That said, I can figure out bits and pieces of an OOL and make tweaks but I probably need a few odds and ends of extra info.

So what I am looking for is this: If you want to use a thermostat device in, say, an RM rule, how does the RM know which settings in the thermostat device should be accessible from the rule? For example, I'd like to write rules to switch back and forth between eco and comfort modes on the thermo. On the Stelpro device page, there is a switch called SwitchMode and that is what I would like to trigger. However, that does not appear as a possible thing to change in RM. RM gives me the change to change mode, but that is a different switch which has the values Heat, Cool, Auto, Off (and these have no effect on the device page). It also has fan mode and heating and cooling set point, but not "switchMode" to eco or comfort.

Any thoughts? Are the choices for a thermostat baked into RM, or is there some way in the thermo driver to tell RM (and others) what can be tweaked?


I don't have this thermostat, but maybe I can help with the RM aspect.
To trigger the 'switchMode' command, you'll need to run a custom action. Choose your thermostat and all the available commands for that device will appear for the choosing.

Good luck!

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Yay! Thank you! That does the trick. (I have to say that it is not totally obvious :-))

I appreciate the help!


One more thing for which maybe there is an easy but not (to me) obvious answers. The switchMode command is actually essentially a push button that switches to the opposite mode. I would like to be confident that I am turning to Eco or to Heat despite the current setting.

I tried making a rule (Switch To Eco) that would only perform the above action if the current mode is "heat". Unfortunately, once again the only state that I can manage to put into a condition is the one that has choices of heat, cool, off, etc. Apparently there are two different states variables somehow somewhere. One is heat or eco. The other is heat, cool, etc. The latter is ALWAYS on heat (since the thing does not cool or anything).

Any more ideas, either for making a conditional based on whether it is in Eco mode, or for some other way to do this?

Thanks so much! This community is so helpful! I hope I can give back some ideas myself eventually!

I found a way around this problem. There is another custom action on the thermostat called "setThermostatMode" rather than "switchMode". If you do it with a custom action, you get to choose an argument which (after staring at the code for a while) in this case needs to be a string "eco" or "heat" (don't use the quote marks when you set it up.) I'd still be interested in how to access those internal state variables, but I don't need that info anymore to accomplish what I want to do.