Well, stuff happens. I felt bad for him too. Retired electrical engineer from California negotiating a tiny backstreet in New Orleans that his GPS misdirected him to.
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Good attitude!
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Well, I made a friend. Seriously, being upset wasn’t going to fix anything.
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FWIW...I can confirm the obvious...an 80 degree bedroom with 70 deg. dewpoint is indeed "quite uncomfortable" as proposed by Mr. Epstein's chart. The windows have been closed and AC has been turned on per wife's request. Closer to 78 degrees and 60 degree dewpoint now and much more pleasant. I'm watching the calculated dewpoint but not using it for control until I have more than one humidity sensor.
Sorry to hear about your fence but at least you made a new friend!
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After installing and configuring the app, the result is a new Virtual Temperature Sensor that contains the dewpoint computed from any temperature and humidity sensor.
Do the following:
Step 1 - Navigate to the "Apps" page, then click on "Add User App":
A new popup window will present all of the User Apps you have installed, including the Virtual Dewpoint Sensor.
Step 2 - Click on the Virtual Dewpoint Sensor tile:
You will then be presented with the app configuration panel:
Step 3 - Make the selections and entries as desired, then click "Done". A new Virtual Temperature Sensor device will then be created, named as entered. The dewpoint computation will take place at the selected calculation update interval.
Hope this helps.
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Thank you!
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So I live in East Texas, where I have the weather conditions you've described, and I've been experimenting, and I haven't been able to make dew point quite work for me.
Do you use dew point for HVAC control at night, while you're in bed? That's the time that seems to be the roughest for us to pin down, and I wonder if it's because being in bed under sheets changes the effective atmosphere I'm experiencing.
Do you have something you've been happy with for nighttime sleeping area HVAC control?
You mentioned targeting dew points in the 55-57 deg F range, but I've found myself uncomfortable at temperatures in the low 70s that had dew points around 47 or 48 deg F.
Nota Bene: I'm using the dew point calculation built in to the Ecowitt driver. It seems to work right as far as I can tell, but I'm confused enough by my results I'm trying to examine everything I think I know.
Yup 24/7 during the summer.
That would be uncomfortably "cold" or "dry" to me. I guess it is whatever one is used to.
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Thanks for getting back to me so quickly!
I'll have to keep experimenting, I guess.
I just had a thought - your Ecowitt is reporting an outdoor dew-point, correct? My thermostat control is based on a calculated indoor dew-point.
I have a couple of Ecowitt sensors, several of which are located indoors. It is the dew point calculated by the driver of those indoor sensors that I control on.
Does that answer the question? I'm still ignorant enough of this I wouldn't know if there were some sort of "Outdoor dew-point calculation" that were different from an "indoor dew-point calculation."
Thanks!
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I think so. Do your sensors report temperature and relative humidity (for each sensor)? If your post those numbers, I'll do a quick dew-point calc and see if the number I get matches the number you have.
I'm just a little flummoxed that a dew-point of 47-50 feels uncomfortable. It certainly is possible (after all, everything is subjective), but I want to eliminate all other possibilities. Would also help if you have temp/rel. humidity numbers from any non-Ecowitt sensors.
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I mentioned this in another thread but you can buy this inexpensive but fairly accurate (within +/- 1%) hygrometer:
I am using it to test and tweak HE & my Konke Humidity sensors but it seems like a good thing for this purpose as well.
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Thanks! I've tried to do the calc myself but it's possible I pulled up a bad calculator or something. I just googled it.
Here are my current sensor values.:
The entries with the deg F unit are the reported temperature, the entries with the % are the RH, and the entries with no unit are the driver-calculated dew points.
These are all Ecowitt sensors - I don't have any non-Ecowitt. I tried some cheapo ones but I couldn't get them to report as frequently as I wanted consistently.
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Boy - that's a huge difference between your bedroom and your living room. Are they are different floors?
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Nope. 
The difficulties in control in this building are that it is just a 24 x 30 metal shop kit with spray-foam insulation. We're living in it until we're able to build a new house.
The "HVAC System" in the bedroom is a window air conditioner on a zigbee outlet.
The "HVAC System" in the 24 x 20 main area is a larger window unit that is self-controlled and that doesn't quite keep up with a Texas heat (you can see the outdoor temperature there) without arranged help from the bedroom unit.
I'm not home right now, but looking at this I'd guess my wife left the bedroom door closed when she left this morning so the bedroom HVAC isn't helping the living room HVAC out at all. 
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So I've just finished "calibrating" my ecobee and a pair of Sonoff temperature and humidity sensors in order to test your dewpoint control method this summer. I was shocked that the ecobee temperature seemed to be off by 2.0 deg. F. and the relative humidity was off by 8%. The $8 Sonoff sensors were more accurate out-of-the-box than the $200 ecobee. I think that at least part of the error is due to internal heat dissipation from the electronics.
Anyway, your previous comments indicate you use a 1.5 degree deadband on the dewpoint value but the screenshot of your Node Red flow seems to show 2.5 degrees. Can you confirm which you've been using?
1.5 degrees for Home/Sleep mode. 2.5 degrees for Away mode.
