I have an aircraft hangar in Florida that suffers from condensation and mold. So we installed a large exhaust fan to aid in ventilation. However with the variations in outside humidity depending on the weather, season and time of day it is possible to suck in more humid air than you are trying to expel. The fan is controlled by a smart switch on a smartthings hub. The methodogy and hardware are as follows.
1. Inside humidity monitored by an Aeon Labs multisensor.
2. Outside humidity monitored by AccuWeather Connect SmartApp
3. Fan switched by GE Z-Wave switch
All hardware is connected to Smartthings hub.. I have tried SmartApps and IFTTT but the problem is persistence. Things trigger at the wrong times.
Here is the requirement:
If "Hangar Humidity" > 60% AND "Outside Humidity" < 60% THEN "Fan Switch" ON
else "Fan Switch" OFF.
If you can help with Apilio then I would be most grateful and willing to make a donation to your project..
PS I can send screen shots on the configuration if you want.