Honeywell T6 Pro Z-Wave Thermostat - Slow inconsistent temperature updates

[ISY4Me]

In the last few days I have started to experiment with a Honeywell TH6320ZW2003 T6 Pro Series Z-Wave Thermostat.   My house runs on heat pumps, so to prevent the auxiliary heat from running, I have programs that run based on the outside temperature and the programs always keep the heat set point within 2 degrees of the actual temperature to prevent my electric bill from climbing when the temperature is above a level that will actually result in heating the house.

I had been using Ecobee 3 thermostats to do this since I migrated away from Insteon and they are doing a good job, but there are times that the lag due to the cloud based communication via the Node server causes issues.  So, I looked for a local control z-wave option and the T-6 looked like a reasonable model to try.

I modified my old Insteon programs to re-align with the available settings on the Honeywell T-6, but I am seeing inconsistencies in the temperature value on the T-6 thermostat and the z-wave node panel within IoP (Polisy Pro with Zeus 700 USB).  In addition, I am seeing long delays in the update of the temperature on the thermostat (sometimes jumping 2 degrees from the last reading) and there are long delays on the updates within IoP even after the T-6 display has updated with a new temp.  I have the z-wave setup option set to update every 0.5 degree change, but the delays described still are present.

Have other users seen the same or is this a design issue with the T-6? The inconsistent slow/delayed updating of the temperature on the T-6 and even slower reporting to the z-wave panel in IoP are the largest concerns.  These make the lag of the Ecobee 3s a smaller issue in comparison.  Are there recommendations for a local solution where the thermostat and the IoP communicate in real time and accurately?

[Bumbershoot]

3 hours ago, ISY4Me said:

Are there recommendations for a local solution where the thermostat and the IoP communicate in real time and accurately?

Venstar ColorTouch T5900 thermostats provide a local API and there is a very good node server to control them from your ISY.  There is a cloud based app to control them as well, but connecting to your ISY is entirely on your local WiFi network, and instantaneous, as far as I can tell.  Heat pumps are supported.  I believe the temperature granularity is one degree, and I use two remote temperature sensors to provide input.  The sensors are supported by the node server.

https://files.venstar.com/thermostats/colortouch/documents/T5900_manual_rev4.pdf

[bgrubb1]

I use the color touch as well. you can set the delta temp. I have mine set to 2 degrees

[ISY4Me]

@Bumbershoot Thank you for the suggestion.  I had not really thought about WiFi... after I decided to move away from Insteon (where I did use the Venstar 1700/1800), I moved to z-wave for control and Ecobee for the thermostat.  With the new Polisy Add-In card coming for Z-Wave/Zigbee/Matter there may be other options possible, but I currently know nothing about Zigbee or Matter.

My WiFi network is very strong, so with my desire to have instant communications between the thermostats and IoP, that might be an interesting approach.  I will read through the link to the manual... thanks.

[Bumbershoot]

36 minutes ago, ISY4Me said:

My WiFi network is very strong, so with my desire to have instant communications between the thermostats and IoP, that might be an interesting approach.  I will read through the link to the manual... thanks.

I may have used too much poetic license by saying “instantaneous”.  Some values are updated in the ISY using the “short poll” value in the node server.  I believe the default is 20 seconds, though you can set it to suit your needs.

[ISYhbsh01]

Question: With the Venstar, can you change the setting from the ISY if it should use a remote sensor or the thermostat sensor?

[Bumbershoot]

2 hours ago, ISYhbsh01 said:

Question: With the Venstar, can you change the setting from the ISY if it should use a remote sensor or the thermostat sensor?

I don’t see anything in the API to suggest that functionality you’re looking for is available outside of the app or the Skyport website (which seems odd — maybe that functionality is undocumented).  You do have sensor data available to the ISY through the node server, so you could possibly write some programs that manage setpoints based on individual sensor data of your choosing.

[ISYhbsh01]

18 hours ago, Bumbershoot said:

I don’t see anything in the API to suggest that functionality you’re looking for is available outside of the app or the Skyport website (which seems odd — maybe that functionality is undocumented).  You do have sensor data available to the ISY through the node server, so you could possibly write some programs that manage setpoints based on individual sensor data of your choosing.

Thanks.

I have the heat thermostat in my bedroom. Sometimes in the winter I like to open the window in my room at night to get some crisp air in, which in turn causes the heat to shoot up. I would love to be able to put a sensor on my window, and have a setting that when the window is open, the thermostat should use a remote sensor located in a different room.  

[Bumbershoot]

1 hour ago, ISYhbsh01 said:

Thanks.

I have the heat thermostat in my bedroom. Sometimes in the winter I like to open the window in my room at night to get some crisp air in, which in turn causes the heat to shoot up. I would love to be able to put a sensor on my window, and have a setting that when the window is open, the thermostat should use a remote sensor located in a different room.  

It might be possible to do something interesting.  If you have a window sensor that indicates the window is open, then set mode to “Off” until the remote sensor drops below “X”.  That ought to work.

[oskrypuch]

On 11/21/2022 at 6:22 PM, Bumbershoot said:

Venstar ColorTouch T5900 thermostats provide a local API and there is a very good node server to control them from your ISY.  There is a cloud based app to control them as well, but connecting to your ISY is entirely on your local WiFi network, and instantaneous, as far as I can tell.  Heat pumps are supported.  I believe the temperature granularity is one degree, and I use two remote temperature sensors to provide input.  The sensors are supported by the node server.

https://files.venstar.com/thermostats/colortouch/documents/T5900_manual_rev4.pdf

Are these wireless remote sensors? Can more than one be used, for EACH thermostat?

I use several Venstar 1700/1800 stats with the Insteon dongles, together with remote sensors. Work great, but if they every give out might need to replace them.

* Orest

[Bumbershoot]

28 minutes ago, oskrypuch said:

Are these wireless remote sensors? Can more than one be used, for EACH thermostat?

I use several Venstar 1700/1800 stats with the Insteon dongles, together with remote sensors. Work great, but if they every give out might need to replace them.

* Orest

I only have one stat, but I have sensors in remote parts of the house.  There are both wired and wireless (WiFi) sensors available.  There is a utility from Venstar that you use to provision the wireless sensors (don’t know about the wired ones).  The wireless sensors can be wall mounted, though they’re kinda big.  See if they meet the WAF before purchasing.  I set them up as fixed IP addresses (IP reservations) and with Lithium batteries, they seem to run forever.  I just put them on shelves where the Mrs. doesn’t notice them, and she’s never been more comfortable.

 

[Clayman]

Getting back to the original question… 

I looked at the Venstar T5900… it looks like a possibility, but availability is extremely low and the cost is very high.  In my configuration, I have three zones, so the cost is an issue.  Programmatic control is more important than a fancy wall unit. 
 

I really agree with @oskrypuch

I used the Venstar T1700 and T1800 for a very long time, but when my PLM started to have issues and the future of Insteon undefined, I switched everything to z-wave and a few node servers using WiFi.  From a responsiveness point of view, the 1700 and 1800 were instantaneous.   Newer thermostat designs have some more heating system parameter control options and a smaller temperature resolution, but these older models worked fine.   I still have the units, so if Insteon ever releases a new PLM, I might consider putting them back to work.

The basic question is… are there responsive non-Insteon thermostats that can be fully controlled with IoP through local control (WiFi, Z-wave, Zigbee or the up and coming Matter)? The thermostat needs to acknowledge temperature changes as they occur, preferably in 0.1 F resolution, but 0.25 F will work… and the change has to be available to the IoP with a very short delay.  
 

Based on my experience with Ecobee… I love the options/settings that can be controlled programmatically, but with no local control, the changes can take up to 4 minutes to register from the IoP - to the node server - to the Internet - to the Ecobee and then back to the IoP. So, I tend to feel that hardware requiring a node server is not going to be ideal for HVAC control. 

[Bumbershoot]

The VenstarCT node server has a default shortpoll value of 20 seconds, though that’s user configurable.  I believe the temperature granularity is one degree.

[oskrypuch]

22 hours ago, Bumbershoot said:

I only have one stat, but I have sensors in remote parts of the house.  There are both wired and wireless (WiFi) sensors available.  There is a utility from Venstar that you use to provision the wireless sensors (don’t know about the wired ones).  The wireless sensors can be wall mounted, though they’re kinda big.  See if they meet the WAF before purchasing.  I set them up as fixed IP addresses (IP reservations) and with Lithium batteries, they seem to run forever.  I just put them on shelves where the Mrs. doesn’t notice them, and she’s never been more comfortable.

 

Do you have some links for the sensors?

* Orest

[Bumbershoot]

1 hour ago, oskrypuch said:

Do you have some links for the sensors?

* Orest

Here’s a good place to buy in the US: https://www.supplyhouse.com/Sensors-14422000

[oskrypuch]

Thanks, US only, but gives me the exact part numbers to look for.

* Orest