Honeywell TH8320ZW thermostat communication problem

Just for the record, I am on my second Honeywell RTH8520ZW from Amazon. Not sure of the difference from 8320 to 8580. The first was returned after LCD display issues and replaced at no charge, this time I’m leaving the light off just in case. Both of them have never had communications issues and worked flawlessly.

I tried several device handlers and settled on @jscgs350 My Thermostat v7, which I now see has been updated to v8.

EDIT: Updated link

Thanks for the info on the @jscgs350 My Thermostat V8 device handler. This is the 1st time I’ve tried to set up a custom device handler. Installation seemed pretty straight forward and the up arrows in the app work fine, but when I use the down arrows the heat jumps immediately to 32C and the cool to 37C. I’m not sure if the fact I’m using Celsius instead of Fahrenheit has anything to do with it. All the other controls are working. I don’t have much experience coding, but from my survey the code all looks fine. Because this device handler works on your Honeywell TH8320ZW I would expect it should work on mine as well. Anyone have any suggestions?

Are the sliders working? I upgraded to v8 but haven’t tried it yet. We are in Arizona and our unit is off now. I will play with it and see what I get.

As soon as I move the heat slider it jumps to 32C and the cool slider jumps to 37C. I really don’t care if the sliders are working. I went to this device handler to get away from the sliders.

Hi @wajans,

I updated the device handler to move the sliders and arrows around, and to make the temperature reading larger by removing the icon because, well, that’s what my wife liked…

Everything is in Fahrenheit, but I will change that. I’ll fix that now, and in fact I shouldn’t have limited it to “F”. That is my fault.

Stay tuned, I’ll be right back!

Hi @wajans, @Whippm,

This update removes forcing units to “F”:

https://raw.githubusercontent.com/constjs/SmartThings-Devices/master/thermostat.device.groovy

Would you mind giving this version a try please?

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Thank you so much for doing this update johnconstatelo! Unfortunately the heat down arrow still causes the heat setting to go to 32C and the cool down arrow sets the temp to 37C. The sliders are now working fine, although at 20C they are all the way to the left, making temperature adjusting difficult. Not that I want to be picky but because 1 degree C is a larger unit than 1 degree F, is it possible to use 0.5 increments? That’s what the thermostat itself uses.

The range feature is in whole numbers, so it’s probably best to not use a range. Let me change that part of the code and look into the down arrow issues. Be right back!

@wajans Can you try this again? The down arrow issue should be resolved.

https://raw.githubusercontent.com/constjs/SmartThings-Devices/master/thermostat.device.groovy

I need to look into the 0.5 increments for the up/down arrows, but I don’t think that’s possible.

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Thanks @johnconstantelo for the continued support of your device type. I don’t know why some people have problems with the Honeywell ZW thermostats, I have never had a problem other than a minor display problem with the LCD.

I updated and everything works in F and I see the first decimal place now, but is is always “0”, even the current temp. The sliders now seem to have full range but the thermostat reports them back to 40 and 99 default. My thermostat must not support decimals even on the panel.

Working wonderfully! Up and down arrows as well as sliders are doing just what they should be doing. Thank you for the timely and effective fix johnconstantelo! Much appreciated. And whole unit increments are certainly functional.

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Try something for me? I ran into this last night. Please clear your browser history for this:

https://raw.githubusercontent.com/constjs/SmartThings-Devices/master/thermostat.device.groovy

I just made a slight change, and added “02-17-2016” under Updates so you know it’s current. I removed all references to any range and up/down arrow limits (this may have bitten you).

Also, make sure to tap on the Configure tile in the app.

Very pleased with the way this is device handler is working with my thermostat!

OK, updated device type, cleared cache, works the same. Here is what I see going on after playing with some system setup functions on the thermostat. The parse returned value is the “function 0600 - Heat Temperature Range Stop” and “function 610 - Cool Temperature Range Stop” as user configured on the thermostat:

8:14:16 PM: debug Parse returned [[value:74.0, unit:F, name:temperature, isStateChange:true, displayed:true, linkText:Thermostat, descriptionText:Thermostat temperature is 74.0°F]]
8:14:16 PM: debug Unit is Off.

This appears to be a normal function and returns the limits of the unit.

In addition, after reading other threads in this community, it appears that most thermostats in this class (CT100, Honeywell ZW) only support whole numbers if the unit doesn’t display them. There are a couple of the very newest thermostats coming out that will support decimals.

Could you please remove the decimals since they aren’t reported? The latest Android ST app handles text bad enough and the numbers go outside the circle. Thanks again for your support![quote=“wajans, post:16, topic:34356”]
And whole unit increments are certainly functional.
[/quote]

Hi @Whippm, that’s interesting on what’s coming in your live logs. Here’s a snippet from mine:

Parse returned [[value:68, unit:F, displayed:false, n

That change should be easy, so give me a bit to look into this?

Thanks @johnconstantelo for all you that have done for the Smartthings community. I have been using several of your device handlers and I really enjoy them. I recently installed a Honeywell z-wave thermostat RTH8580ZW1001 which Smartthings does not recognize as a Honeywell and added it as a generic Z-wave thermostat. I switched to your handler for the TH8320ZW which is tremendously better. I would like to ask if it is possible to add the “Permanent HOLD” feature? While I could remotely change the temperature set point, but when the thermostat moves to the next programmed slot, it will automatically change to the temperature programmed for that slot. It would be very useful to be able to permanently hold a temperature remotely as I could do on the unit itself.

First, thanks for those comments, I appreciate that!

Unfortunately that’s not supported by the thermostat via zwave commands. Page 12 and 13 describe what the thermo can do:

The only workaround would be to always keep the thermo in “hold”, and then to use a SmartApp to control programming. Here’s a link to a discussion on one that works really well:

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Thanks @johnconstantelo for the reply. I guess I shouldn’t need to program the thermostat when I could have Smartthings control it all together. I finally realized that the Smartthings hub could provide all the programmable capabilities of the thermostat and more. I setup a few automation routines to turn the heat on/off based on mode and arrival/departure and it’s working great. Since I have two heating zones, I installed two z-wave thermostats. I only wish Smartthings would update the software to allow independent temperature settings for each thermostat. For example, in the “Good Night!” routine, it allowed me to select and set both thermostats, but only allowed one temp setting to be applied to both thermostats. Unless I add another routine, I cannot set the upstairs temp to 65 and the downstairs to 58. I should send a comment to Smartthings support and see if they are receptive to improving on the next update.

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Yeah, I completely agree. Because of how many devices and rooms I have in my environment, I ended up creating two Routines, but I would have preferred to keep it simple and have just 1.

Looks like this got Hi-Jacked.

I poached the Following Solution from another forum https://forums.homeseer.com/forum/thermostat-hvac-plug-ins/thermostat-hvac-discussion/97075-honeywell-z-wave-th8320zw-won-t-connect-to-z-wave-solved
and it solved my problem with Getting the Thermostat to Connect to SmartThings.

"Honeywell Z-wave TH8320ZW won’t connect to Z-wave - Solved!
August 23rd, 2016, 09:00 AM
I hope this helps others out there-- hopefully you won’t waste a couple of hours trying to figure out what is wrong with your device.

I bought a Honeywell TH8320ZW thermostat to work with my Samsung SmartThings hub. After getting it turned on, the top of the screen would almost instantly say “Communication failed”. I would try to add it to the Z-wave network (just like it says in the manual) and it would do one of two things: 1) say “Adding to Network” but it would never do anything for a few minutes, or 2) almost instantly say “Action Failed”.

The problem is this: the Z-wave component of the circuit board is not properly connected to the main circuit board. The two are connected by four thin pins, and the housing is spacious enough that they easily become disconnected. To reconnect them, open the housing by peeling off the front housing (the one around the touchscreen), it should snap off, and this will expose the screen casing. There are two tabs on the sides of it to push back, then the whole thing can come loose. You can remove the main circuitboard now, and then you’ll see the Z-wave board just underneath (still in the housing). Try to now push them back together (being very careful to align it properly). You can put the thermostat back on the wall without the front casing on, and try to set it up again and see if it will connect to your Z-wave hub now. This did the trick for me.

Hope this helps someone!"

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