Honeywell YTH8320ZW1007 Thermostat Programming Through Hub

I have two of these thermostats, the Honeywell YTH8320ZW1007/U Z-Wave Enabled Programmable Thermostat. I’ve been having some issues with the thermostat going off-schedule mid-day and opened a case with Honeywell.

They indicated that while the thermostat has a built-in scheduler, it is best if the controller manages the temperature setpoints for the unit.

I explained I had SmartThings and they had no idea how to help.

Does anyone know how I can control the 7-day program scheduler - or make my own schedule - for this thermostat through ST hub?

You’ll need a SmartApp to control your thermostat, check this out. Don’t have one so I haven’t tried it but here:

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Looks promising, but I don’t have external temp sensors, nor contact sensors for this to work. I did find a 5-2 day programmable smartapp, but it’s not quite working.

Guess I’ll keep digging in. Will appreciate any other thoughts.

Actually, this one seems to be working. Looks like an updated version of the one I was playing with.

According to the live logging, it appears to be doing what it should be. I’ll continue to kick the tires

Yea I’ve seen that one before. I’d stick with that for simple control.

Two thought here,

  1. Watch out for this thermostat as it has a “learning mode” which drove me nuts for a while. I had schedules set and it would never work on time, it was always before or after about the time I set. Once I programmed the smart mode off it was rock solid.
  2. Try to get away from procedural programming and move into an event driven paradigm. Instead of hard scheduling your thermostat and having you work around it get presence sensing running and mode defined. Clear all the schedules and have the thermostat change temperatures based on your presence and mode.
    Use the custom “Better Thermostat” or “CT30” code as they work better than the ST default and are fixed for F and C

Yeah thats a good idea. Need to pick up some motion sensors and stuff to make this happen.

Thanks for the tips. I’ll need to go wipe out the smart mode on the thermostat (guess I’ll need to read the owners manual on how to do that)

I don’t have much based on motion, mostly presence. 2 cell phones and 2 fobs are linked to the house modes of Away, Night, Good Morning and I’m Back. The temp is set down when we all leave the house (Away) or it’s Night mode. In the morning the Good Morning is triggered when I hit the bathroom and up comes the temp or if someone comes home in the day.

I am trying to get the thermostat to respond to routines. I see the “routine” temp command sent to the thermostat on time, where upon receipt, the thermostat changes the temperature to another value. It is not clear where these other temperature settings are coming from.

I have deleted modes and worked to limit the routines that have any impact on the thermostat. Still I see an override coming through.
Is this some of the “learning mode” going on?

In the past, I used the WiFi Honeywell thermostat version which was great, but I did not set it up to work directly with SmartThings.

Any help on the subject is appreciated. I am using code from drsprite which resolved many “other” issues.


I’m curious. What if you use the scheduler built in to the thermostat and then override that with ST? Does it go back to the schedule at the next time?

I’m wondering the same. For instance, for my Home mode, the thermostat is set for 66 degrees for heating and the schedule is turned off in the Lyric app. The thermostat doesn’t seem to respond to either.