Vivint Element CT200 Thermostat Spontaneously Changes Heating Setpoint

Hardware Home Automation
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Does anyone have experience using the Vivint Element CT200 Thermostat with OpenHAB?

I purchased and installed a Vivint CT200 Thermostat (https://www.vivint.com/ppc/element-thermostat and https://www.cd-jackson.com/index.php/zwave/zwave-device-database/zwave-device-list/devicesummary/938). Although it’s intended to be used with the Vivint service, it’s seems to be a perfectly valid ZWave device, and I’ve successfully included it in my ZWave network (after updating the device database).

I have some rules to set the heating setpoint, and they all seem to work; however every morning the thermostat seems to change the setting entirely on it’s own. Yesterday morning at 03:32:01 AM PST, the thermostat changed it’s setpoint from 60 degrees F to 69 degrees without any user input or rules being added. The only entries in the log were:

2018-11-19 03:32:01.217 [vent.ItemStateChangedEvent] - ZWaveThermostatHallway_SetpointHeating changed from 6E+1 °F to 69 °F
2018-11-19 03:32:01.233 [vent.ItemStateChangedEvent] - ZWaveThermostatHallway_ThermostatOperatingState changed from 0 to 1
2018-11-19 03:32:01.252 [vent.ItemStateChangedEvent] - ZWaveThermostatHallway_SensorTemperature changed from 67 °F to 67.5 °F
2018-11-19 03:32:01.270 [vent.ItemStateChangedEvent] - ZWaveThermostatHallway_SensorRelativeHumidity changed from 37 to 38

Again, this morning, the setpoint changed from 60 degrees F to 65 degrees, with seemingly no outside influence:

2018-11-20 01:14:48.513 [vent.ItemStateChangedEvent] - ZWaveThermostatHallway_SetpointHeating changed from 6E+1 °F to 65 °F
2018-11-20 01:14:48.532 [vent.ItemStateChangedEvent] - ZWaveThermostatHallway_SensorTemperature changed from 67 °F to 65.5 °F

I thought that this thermostat was “dumb” in that it wasn’t programmable and only reported status and accepted commands via ZWave. Was that conclusion incorrect? Does this thermostat have some sort of intelligence of which I’m unaware.

Any help in trying to figure this out would be helpful. I think I can counteract these odd setpoint changes with some well-crafted rules, but if someone can shed some light on why this behavior is occurring, I’d greatly appreciate it.

Thanks.
~ Bryan

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Bryan, did you ever work this out?
I am considering buying a number of these ‘dumb’ z-wave thermostats to be even dumber, to ONLY function as a supplemental display and user-input device.

The main idea is that the 'stat wouldn’t even be connected to any HVAC equipment at all. It would just be there to show a passer-by the local temperature, (possibly) detect local presence (motion), and collect another temperature datapoint, and of course allow setpoint changes using its buttons.

The real HVAC will still be controlled by a different (more capable) thermostat, and OH would sit in the middle to receive the setpoint change from the device, and push it to the real system. Of course OH would also push any setpoint changes made elsewhere (e.g. OH UI) the other direction to the device, so that it would show the current setpoint on the screen.

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Nope. I never did get this to settle down. I ended up buying a “GoControl GC-TBZ48 Z-Wave Plus Thermostat”. It doesn’t look as nice, but it works. Although it does have some weird quirks like it will accept setpoints in Fahrenheit, but seems to want to report the temperature in Celcius. Although it may be some oddity in my OpenHab configuration; I’m not sure.

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