[brewinathome]

I built one, made video and posted it to youtube if interested
http://www.youtube.com/watch?v=uka0iksiSTw

[weithman5]

nice

[richardt]

Good post/tutorial.  In principle, what do all the various components do (layman terms, please)?  I'm not an electrician.

Since the thermistor is contained within the Honeywell box thermostat, does the whole thing go in the fridge?  If so, won't condensation be an issue?  I'd prefer to keep the bulk outside the refrigerator or keezer.

Would buying a cheap thermistor with a longer cord online and wiring that to the thermostat keep the bulky box outside the fridge?  Something like this, perhaps? http://cgi.ebay.com/Mini-LCD-Digital-Fridge-Freezer-Farenheit-Thermometer-/220544704982?cmd=ViewItem&pt=LH_DefaultDomain_0&hash=item33597d21d6

I've thought about building one, too.  Just don't have the experience or skills to do it. 
The recent Ranco thread has me second guessing any $50-100 purchase for an item of poor or questionable reliability.

[brewinathome]

Like you I am not an electrician.
I saw this post at realbeer: http://www.realbeer.com/discussions/showthread.php?t=19023
I found wiring this was easy.
the SSR acts as a switch to turn power on and off to the plug for the Fridge/freezer or heater
the power adapter supplies power for the thermostat to turn on the SSR


I did find this tutorial after I had built this one, might interest you as well.

http://www.homebrewtalk.com/f51/ebay-aquarium-temp-controller-build-163849/

if you have any other questions, please ask.

[paulcgi]

oops.. sorry this is late, I haven't been on the forums in ages and had to register a new account.
the post from Real Beer is mine.
What you can do is de-solder the thermistor from the circuit board inside the temp controller, solder in a bit of wire to the board, then solder the thermistor to the end of the wire. This, in effect, makes the setup remote sensing.
What I did with the last one I built was put the whole thing inside an 2-gang outlet box. Then I used a wall plate with 1 outlet and 1 switch to cover the box, with an outlet on one side. Then I mounted the temp controller on the wall plate over the spot where the switch would be.
makes a nice compact unit.
The really nice thing for me at least is that since my kegerator is in my barn, I can unplug the freezer, plug in a small heater and switch the temp controller from 'cool' to 'heat' and continue using it in the winter

[weazletoe]

So I'm only like a year late on this one, but I was just checking out some old to me threads. I had a question about the diagram....Wouldn't you wanna go from "Y" on the stat, and not "G". Y is your cooling terminal, and G is your fan. Also, I think you would need to put a jumper between RC and RH, as you're dealing with a single transformer system here. I could be wrong, and normally am, just asking....