Hey all, I thought I was in luck with the Honeywell YTH8320ZW1007 thermostat. Looks just like the Vision Pro but ahh, they removed humidity control.
So any options other than something like the pricey Ecobee 3 at $200+?
Not sure of what other options are out there, but the Ecobee is an excellent option. Assuming that you have a relatively accurate humidity sensor inside and you’re simply wanting to use the cooling of the A/C to control humidity, you could just use PLEG to lower the A/C a degree or two when the humidity gets to a set level. If you’re running a dehumidifier setup, it is still possible to control it but I’m sure it would be a bit more involved…
That’s an interesting option. I hadn’t thought of using pleg. And I guess I would be able to make it go up to 3 deg. below set point (whatever that is) and not be stuck with a specific number?
How are you controlling the thermostat now? If you’re managing it with Vera and not expecting it to change at the thermostat itself, then you could simply build your conditions so that it “falls back” to the condition is was originally in. I do this with several virtual switches to control automatic locking of my entry doors. When the wife and I are both gone but someone is still here, the doors automatically lock 30 seconds after they are closed. I did this because the kids are NEVER in the front of the house and they wouldn’t hear someone cleaning out the living room. I have a few other cascading conditions as well. They work nicely.
What climate do you live in? I’m in Florida where the humidity is quite high but since I put the Ecobee in, I’m aware that the humidity rarely gets above 55% inside. Anything below 60% is comfortable. 
Your conditions may vary but there are definitely cheaper methods of handling this issue. I chose the Ecobee route for a number of reasons, one of which is the occupancy sensors that can be added to it. I use them in Vera to tell me what rooms are occupied as well as the temperature in those rooms.
This is a clients house. We do building performance work and have recently added smart home controls to our offerings. They currently have regular programmable thermostats and are wanting a lower cost alternative to the Ecobee 3. We are in coastal NC so really need the humidity control.
What I would want is for the script to say something like “if rh is above 55% drop set point 1 deg., if rh is above 58% drop set point 2 deg.”
Well, I’m not too sure if I’d want to experiment with a clients house first, but that’s just me. Assuming that the house is fairly air tight, a humidity of mid 50’s shouldn’t be hard to accomplish. I live in central Florida and although the outdoor humidity is currently 83% and I’m in a 30 year old house (with a few upgrades), the indoor humidity is currently 49%. Thermostat is set at 77 as I’m home but drops to 79 when I go out. I haven’t implemented any kind of humidity control yet as I haven’t had the need. Mind you, I’ve only had the Ecobee for a few weeks so I’m still gathering data…
Anyhow, if you’re going to control humidity in this fashion, I suggest that you monitor ALL doors and windows as part of the process. Otherwise, if someone opens a window and doesn’t shut it, humidity climbs and you’re cranking the A/C down incrementally for no gain. I intend to limit my exposure to this by shutting down the A/C if a window is opened or if a door is left open more than a few minutes. This will prevent a lot of wasted energy as well as account for the periods of the year that we regularly open windows or leave the patio doors open because it’s cool outside. LOTS of things to consider when automating things…
For the Europe market there is the Secure SES303 model at around ?62
If you are writing the script anyway, then you could use a separate humidity sensor, like the Everspring ST814. Or one of the multi-sensors like the Aeotec MultiSensor 6… Obviously an additional sensor takes up space and not as pretty - I too am disappointed the Honeywell doesn’t have humidity - but as I needed three of them for my house, it made sense to go with those anyway…