It appears that the default display setting for the IR2900 is Celsius. For those who need to change the display to Fahrenheit it isn't defined in the user manual (that came with my device) what parameter needs to be changed. I reached out to MCO Home and they provided the following:
The Hubitat driver which became available in release 2.3.9.135, does not provide a method to modify parameters. I used the basiczwavetool driver to set parameter 1 to a value of 1 (Fahrenheit) [byte size 1]. Set parameter 1 to 0 for Celsius should you have the opposite problem.
It would be great to have either a toggle (F/C) in the IR2900 driver and/or the ability to set parameters. Providing the driver source code on github would be great so that the community can enhance it.
The "normal" way to handle C vs F is that the driver queries the hub for what the user set in Settings: Hub Details:
If MCO Home kept that a "secret" (not in their developer documentation,) then Hubitat would have little choice but to stick to what was documented.
Now that you've found a solution, let's tag a Hubitat Engineer @mike.maxwell and ask that they update the internal driver to follow the temperature scale pattern they've already established.
I've read that parameter description three times and, while I understand what each word means individually, I have no idea what they are actually trying to say.
I also cannot find this product on the Z-Wave Alliance website (hoping the certification docs would have parameter descriptions) or any manual for this particular model on the manufacturer's website.
If this seems like it would be a useful addition to the built-in driver, I can help with that -- as long as someone can say what it actually means, and ideally whether there are any firmware restrictions that would affect if/when it is available. If this affects how the device reports to the hub, then, as mentioned above, this is usually set automatically by the driver according to your hub preferences. It looks like the driver is already trying to accommodate that.
The built-in driver actually does have knowledge of a few configuration parameters that weren't exposed in the UI, I think, by accident, but this wasn't one.
All that being said, the new "Generic Z-Wave DT Thermostat General" driver should also work for this device, at least as far as offering all configuration parameters the device offers should go. This is in platform 2.4.0 (and newer) only.
