Zen Thermostat runs fan only, but says heating

I switched to a Zen Thermostat and for some reason when it is supposed to run the heat it will just run the fan.

In the dashboard and in the devices screen it will show the current state is heating but really just the fan is running. Usually it will run for about an hour then either shut off and turn back on, or the heat will kick on.

I tried an old thermostat and it kicks the heat on every time, so it's not the furnace. More often than not it will just run the fan. Has anyone else had this issue with the Zen Thermostat?

Does the thermostat operate properly when controlled physically?

I tried interacting with it manually a few times and so far it has worked each time. I can try disconnecting it from the Hubitat and letting it go for a day to see if that is the case. I am using the Zen Thermostat driver and haven't tried the generic one yet. I don't think that should matter though.

The Zen driver is the correct driver for that device.
It's possible they released a different firmware.
But yeah, I would remove it from Hubitat, then add it back in a few days, let me know how that goes.

Are you running it with the C wire attached?

Okay I'll remove it from Hubitat and report back, and I'll check if there is a firmware update for it.

I am running it with the C wire.

Did you configure your zen with how your hvac is wired? Asking bc we recently went from radiant heat(boiler) to a nee hvac system and had to re configure our zen to work with the new system. I have noticed that at times it doesn’t update on he. Not sure why. It’ll say the fan is on and or it’s heating and it’s not. Only does it occasionally tho.

and you have batteries installed correct?

@murv82 I did double check the configuration. I have a single-staged furnace with single-staged cooling and fan control for my system. I used 11B as my code.

I do have batteries installed as well. They are the batteries that came with the device and I haven't tried with new batteries yet. That is my next thing to try.

Okay I've had it disconnected from the Hubitat for almost a full day now, but I have still run into the issue, so I think it's safe to rule out the Hubitat being the cause.

It worked fine for the majority of the day yesterday but noticed that when I changed the temperature is when the issue started happening again. I had the Hubitat change the temperature based on my presence so that kind of makes sense now. I will contact Zen to see if they have a solution.

Thanks for the troubleshooting help.

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