Thermostat Scheduler - Controller confusion

jwvincent2 · April 21, 2022, 7:58pm

Hi There, I'll start by apologizing as I see many posts that are somewhat centered around my issue, but nothing that seems to fully hit on all aspects of my (or HE's family of thermostat apps/drivers).

Setup:
Physical Thermostat: Honeywell T6 Pro (Zwave)
Driver: @bcopeland 's Advanced Honeywell T6 Pro driver
Apps being used:

Thermostat Controller (Link to HE official Documentation)
Thermostat Scheduler (Link to HE official documentation)

Working back from the end of the line which in my mind is the Scheduler.

Scheduler is saying my current time period is set to overnight. This makes no sense as the time is currently 12:30 pm and it should be in day mode.

Next, I'm getting different setpoints on my thermostat (not controller) device page than what is supposed to be happening according to the scheduler.

In scheduler:

On device page the cooling set point says 70 when it should be 68 according to the scheduler:

Moving along to the controller app:

I'm generally confused on what I'm supposed to be seeing here after following the documentation. Here is the screenshot that covers most of the following issues:

Question: shouldn't the cooling setpoint of the controlled thermostat match the setpoint of the virtual controller device?
Question: What does the Control Offset do? I've looked through posts and documentation and can't figure it out.

Since I have my control offset at 2.0, what should I expect to see on the device page and even the "Main thermostat" box on the controller app settings page?

This could potentially explain why the device page shows 70 as the setpoint even though I would like it to be 68 (even though that's the setting for overnight mode, which the scheduler should not be set to - but we already covered that earlier)

At this point this is where my confusion takes over and I'm no longer sure if the apps are working together correctly, or if I'm just looking at it wrong, or likely I'm just doing something wrong.

The controller is set to control the thermostat, and the scheduler is set to control the controller...

@bravenel I'm hoping you might be able to provide some insight here as to what might be the issue. Thanks so much in advance for everyone's help in clearing this up!

bravenel · April 21, 2022, 10:17pm

Thermostat Controller takes over the controlled thermostat's logic for knowing when there is cooling demand and when it is satisfied, essentially gutting it as a thermostat. To do this, it drives the controlled thermostat into cooling or idle by controlling its cooling setpoint. To cause the controlled thermostat to call for cooling, it sets its cooling setpoint below the actual target. Then, when the target is reached, it sets it above the target. In theory, this should cause the controlled thermostat to call for cooling, and then to stop calling for cooling and go to idle. The amount by which it sets it to below or above the desired target is the Control Offset. (All of this could be applied to heating, just in reverse.)

In theory, yes.

To get you situation sorted out, you have to take it apart and deal with each piece. Start by getting the Thermostat Controller working as you think it should. See if it will control the real thermostat appropriately. One way to test is to use Virtual temperature sensors instead of real ones, so you can fake what the environment is (they allow you to set the temperature they will report), and see if the controlled thermostat acts as you think it should. Once that is working, then you add Thermostat Scheduler to layer in times of day.

This stuff can be confusing, and you just have to work it point by point, starting with the real thermostat device page, and how it behaves when controlled by Thermostat Controller.

jwvincent2 · April 22, 2022, 4:44am

Thanks so much, @bravenel for answering those key questions. Your responses made me wonder if my thermostat (Honeywell T6 Pro Zwave) is more capable, and therefore not a good candidate for using the thermostat controller app.

I'm using @bcopeland 's community driver (link to the HE Community page and Link to the driver code on github) which reveals most of the advanced (installer) setup functions.

Here's are screenshots of the advanced settings on the HE device page:

I read through the thermostat installer manual to go through the advanced set up as a fresh start and noticed the Auto Differential option. This seems to be a similar function as the control offset in the HE thermostat controller app.

Here is the text from the thermostat's manual:

With this in mind, if I change auto differential setting to 2 on the physical device and control offset setting to 2 on the controller app, will this cause any problems with either of them?

@bcopeland since you have (or had) this thermostat, do you use the "Thermostat Controller" app with the T6?

I'd like to use the app mainly for the remote sensor function since the thermostat only directly supports wired remote sensors.

@bravenel or @bcopeland - If I do use the thermostat controller app, can you confirm whether I should set the auto differential setting on the physical device tomatch the control offset setting in the virtual controller, or should I leave one of them at 0? My worry is if I set both of them to 2, I would cause the controller to over/under compensate the offset?

Once again, thanks so much for the help!

bravenel · April 22, 2022, 4:51am

These two things are completely unrelated, and you probably should not be messing with advanced settings in the thermostat itself -- especially since you are turning it into a dumb slave. Leave them as set by default by Honeywell.

The only reason to use Thermostat Controller is to incorporate extra temperature sensors in guiding the thermostat behavior. The only reason to do that is if you have a badly placed thermostat, or very uneven passive heat gain/loss in your home varying during a single day. These are somewhat unusual circumstances.