Resurrecting this old thread...
I control my fermentation chamber with iobridge module and components. I use their free dashboard to control my fermentation chamber temperature presets, monitor and graph the temperature, turn on or off my fan, measure ambient chamber temp, and measure beer temp (with a thermowell). My fermentation chamber is a chest freezer. I also have a little space heater in there. I've been meaning to write it all up, but I haven't been motivated to do it yet. Here's some brief details:
* I have two temperature probes connected to the iobridge module. One measures ambient temperature of the chamber. The other measures the beer temperature. I can control the temperature environment either by chamber temp or by beer temp.
* With the free iobridge account you can display all sorts of information about the sensors. I have temperature fields, preset temperature widgets, temperature graphs, etc. The iobridge account also gives you an extensive rules engine. I use rules to turn on the heater or freezer based upon temperature readings from the thermometers.
* I use x-10 appliances that are connected to the iobridge module (similar to an arduino or raspberry pi) to turn on/off the freezer or heater. The rules in iobridge allow me to keep my chamber at whatever temp i'm shooting for. I can make lagers in the middle of summer and I can make ales in the dead of winter.