Attic Fan Remote Control
Date: 01.26.16 - 6:09pm
My house is prone to icing so I had to install a exhaust fan that turns on when the humidity reaches a certain point. BUT..you have to go up there and manually set it, and the setting is different for summer vrs winter.
My attic is no fun to get up into, and tuning the setting and there was no real way to keep an eye on what the actual humidity was up there.
Arduino to the rescue!
We use a servo to remotely turn the physical humidity setting knob, and added in a small oled screen and a temperature / humidity sensor to keep an eye on the conditions up there.
Final installation is battery powered and installed in a downstairs closet. Will be MUCH more convenient to use and monitor now!
The project is open source: Source code here. All in all the project probably took a full days labor to get the code just right and do the physical installation.
Ok so its been a year since I have installed this. Being able to check what the temperature and humidity is up in the attic and when ice forms has been interesting. This remote control has been working flawlessly.
I am very glad I have it because I find myself changing the setting allot depending on conditions.
This tells me I am going to have to replace the factory controller completely. Its basic controls are not sufficient to determine when the fan should be on or not or when icing conditions are present.
here is the logic necessary:
Today its 40deg out and raining, the fan would be on the entire month of march and april!
So I will need to get a clean reading of outside temp as opposed to attic temp which never drops below 40.
In the meantime being able to tinker with it and manually adjust without having to wade through insulation is acceptable. And I really need the fan on in the winter to prevent icing so must have.
Currently the logic the factory controller support is: