Design Help for Building HVAC


1) Give a description of the problem
I work at a church that has several things happen in the building during the week. We have several Honeywell WiFi thermostats. I’m thinking I may purchase a smartthings hub to control the church thermostats based on a webcore piston like I do at my house. My house is only 2 thermostats, and my church will be 26… I’m wondering if that will be a problem for smartthings or webcore. Honeywell has assured me 99 is the number they tested at.

2) What is the expected behaviour?
I want to edit a few lines each week (in webcore) to schedule on/off and setpoints for the thermostats. That way I can look at a calendar and then program my thermostats out for the week.

3) What is happening/not happening?
The Piston I currently have will function fine based on weather, but can I use a time/date as a trigger instead?

**4) Post a Green Snapshot of the piston![image|45x37]

5) Attach logs after turning logging level to Full
3/8/2021, 5:09:46 PM +271ms
+10144ms ║Piston waited at a semaphore for 10081ms
3/8/2021, 3:09:46 AM +341ms
+10078ms ║Piston waited at a semaphore for 10015ms
3/7/2021, 5:09:46 PM +215ms
+10095ms ║Piston waited at a semaphore for 10020ms
3/3/2021, 3:09:46 PM +231ms
+10096ms ║Piston waited at a semaphore for 10019ms
3/3/2021, 1:09:46 AM +462ms
+10579ms ║Piston waited at a semaphore for 10503ms


My comments here are just an observation…

I don’t think so. Webcore can easily control as many devices as you like. But my concern would be trying to control too many thermostats at the same time. I don’t know what it would be, but I imagine that each thermostat may require a period of time to make changes before the next command can be processed. I’m talking maybe less than 3 seconds here. So, for instance, when you change the mode (Heat, Cool) of a thermostat, you might need to pause a moment before setting the temperature. Webcore commands may fire off so fast that they get missed or ignored by the thermostat.

You mean like…

I would also consider writing separate pistons for heating and cooling. And possibly even further divided by each individual room/zone in your church. Debugging would be far easier on a room by room basis than trying to locate a problem in a large, “church-wide” piston. YMMV.


Thanks for the input. It’s a work in progress and I’m going to try a few things…