Hi,
I am a relative newbie with Hubitat configuration, primarily using light switching rules and timers so far. I recently found @storageanarchy's Ecobee Suite, and am in love so far. However, I'm hoping I can get some suggestions / direction on the best way to achieve something probably simple, but that I'm currently struggling with.
My house is ~3,600 SF. There is an existing set of duct issues which I won't go too deeply into but the pertinent piece is that at some point, there were two thermostats in the house controlling 2 forced air 'zones' that were off balance. At some point someone removed the second thermostat and locked the 2 dampers in the vents to open, now controlling the house with only one zone. As a result, one side of my house gets vastly more pressure at the vents and is more efficiently cooled/heated.
I still have the motors to control the vent dampers, and have recently ordered the Zooz multi relay. The motors are simple 24v motors, and I can avoid all of the controller boards and just use the relays to power the motors for a set time to open / close (the dampers spin in one direction, so the motor powers for x seconds to rotate them 90 degrees).
Problem #1 - programming the multi relay to create an 'event' that powers the motors for x seconds to move exactly 90 degrees. My first inclination was to create a custom app that can be called to do this, but is there a simpler way?
Problem #2 - setting this up with Ecobee Suite. I have 3 room sensors, the thermostat, and a handful of other temp sensors around the house on both zones. I need to average each zone's sensors together, and set them up as such in Ecobee Suite, right? And then what helper module do I use to trigger the actions, per zone? Would that be mode/switch/program helper?
@storageanarchy here...
This may be tricky, if your dampers actually work as you describe. Usually, these dampers are spring-loaded, such that they are open when no power is applied to the damper motor. When power is present, they close. If they do work as you describe, you might actually want/need the circuitry that controls them, because there is no way you will get sufficient precision to power them to EXACTLY 90 degrees repeatedly - over time they will surely drift.
The Smart Vents Helper can probably do what you want, as it can also control switches and dimmers in addition to Econet and Keen vents. It can use multiple temperature sensors, take the average, and open/close the vents/dampers based on the comparison to the thermostats' setpoints (or manual setpoints, or a "virtual thermostat's" setpoints).
But first you have to figure out how to turn an on/off switch command in Hubitat-land into something that opens/closes your dampers...reliably.
Thanks! I need to investigate the actual damper, I made the assumption of the way they work based on the motor, as supplying 24v to the motor makes it continuously spin in one direction. I’ll report back.
@storageanarchy I confirmed that the dampers work as you described - seems a bit counter-intuitive and like it would quickly burn out the motor, but they were developed by people smarter than me!
So for your last point, I think I can just do that by activating the relay when I want a zone to be OFF - they fail open. Then I'm hoping there's a function to ensure all switches are "off" (meaning both ducts are open and I'm not constantly running the damper motor) when there is no call for heat / cool?
That's great.
Now, figure out if you can REVERSE the power, so that instead of normally open when no power, they operate normally closed. This would make your life a bit easier.
If not, go the other route and cross-wire them such that they close the OTHER zone when they need more Heat/Cool.
The power source should be the HVAC system itself, and it SHOULD cut power to the dampers when nothing is running.
There was probably a multi-zone circuit board at one time - that's what probably handled all the open/close logic. Remember, a thermostat is just a switch with a lot of logic to figure out when it should call for (demand) heat/cool. The HVAC unit + zone controller would be responsible for opening/closing zones based on demand. It is simpler to keep the zone controllers engaged, and then you are using your relay to turn on/off the "demand". When your remote zone is too hot/cool, it turns on the demand, so that whatever is blowing also goes to the remote zone...
I really like the idea of powering off the HVAC, that will make them fail open when the HVAC turns off. I know I can't reverse the power, it's based on the springs in the damper itself, and I would want it to fail open in case of any issues. And I think I'll run them independently so I can one or both open at any given point.
As for the circuit board, I do still have it, but it looks to be very old and I can't find anything related to operating it online anywhere. So I think I'll just replace that with the relays and run it through HA.
Thanks again for the assistance, I'll update once I get things wired up & can start testing.
@storageanarchy I now know what you meant by wanting to reverse the power, as your app can only currently control opening of vents. So here's my formal enhancement request 
- please add a toggle for whether you want the switches / vents to turn on or off at your selected actions.
I don't think this will work, as if both zones need cooling/heating, then both vents will be closed, which can never happen or I'll damage my HVAC equipment.
Again - that's why there are things called "zone controllers"...methinks you really should have one, instead of hoping that some combination of device drivers and applications are going to create the equivalent.
As for the enhancement request, there is already a simple solution:
- Create a Virtual Switch device, and have Smart Vents turn this device "on"
- Create a new Simple Automation Rule that turns "off" your damper control switch when the Virtual Switch is "on", and vice versa
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Sorry for the prior short response.
Your zone controller protects against both sides deciding they don't want heat/cool at the same time, so you will have to write logic that prevents each side from closing if the other side is already closed.
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