Laptop controlled fermentation chamber

A little background: I've done 3 Mr. Beer kits at room temperature and 2 better bottles with water/ice buckets temperature control. I've been very disappointed with the off flavors that I'v narrowed down to being a result of poor fermentation temperatures.

My dad, being a computer programmer, found a Linux Journal article dealing with this exact situation and it had a cheap alternative to the Ranco temperature device. Here's what I needed:

TEMPer USB thermometer
x10 controlled outlet/controllers
Heating pad
Refrigerator
Laptop running Linux

I was able to get the refrigerator and laptop for free and the other items are relatively cheap.

This is how it generally how it works. The outlet is wired into the wall with the top being controlled and the bottom plug always being "hot". I plug the fridge into the top plug and into the bottom I plug a receiver with the heating pad plugged into the receiver.

The code is simple (I can understand the logic, but don't understand Linux). Let's say you want it to maintain about 60F. In the code there is a tempmax and tempmin. These are set about 2 degrees apart so that the refrigerator isn't turning on and off with a lot of frequency and stressing the compressor. Essentially if the fridge gets below tempmin, the fridge turns off and the heating pad turns on. If it gets too warm, the fridge turns on. The program is always running and spits out a temperature reading on the screen.

I'm hoping this will help the quality of my brews and I thought it was a neat alternative to a Ranco or similar device

A picture is worth 1000 words!! Would love to see this in action.

Honestly I brewed about 10 Mr. Beer kits and not one of them tasted any good. I finally threw all that equiptment away, switched to 5 gallon extract kits and my beer instantly started tasting better. I'm sure people on this forum will say otherwise but I think Mr. Beer kits are absolute garbage.

TriangleIL said:

A picture is worth 1000 words!! Would love to see this in action.

Click to expand...

+1. We need pics.

Do you think you'll need the heating pad AND the fridge? I find that my ambient temp is normally higher than my target ferm temp, and I can get away with just the cooling side of things. It seems like if you use both you'll be overshooting the cooling, followed by heat, overshooting the heat, followed by cool...etc. Does the program your using predict thermal carryover and know to shut the cool or heat off in advance of target temp? My carboy usually drops a degree or two AFTER the ac unit in my chamber turns off.

Hrm... this sounds like a fun project. I was going to setup a fridge for fermenting anyway.

This sounds very cool but you need to ask yourself if this is going to be as efficient as a Ranco controller or as easy to use as Ranco



* Also, I prefer to keep the fridge running and use the heating pad to warm the beer. Will save the compressor from cycling too much

In college my kegerator had a broken thermostat, so my roommates and I rigged up something very similar. It worked great most of the time, but a few times the linux computer locked up and sometimes we ended up with frozen beer if the computer locked up when the compressor was on or we got warm beer if it locked up when the compressor was off.

One of the first things I did when I graduated was to buy a cheap analog temperature controller. It's worked great ever since. And you save a lot of power because you don't need to have an extra computer on just to run your fermentation chamber/kegerator.

So I can't upload photos but I can link you to them:

http://picasaweb.google.com/111974984697998602419/005?authkey=Gv1sRgCLfhw-er_JLIaA&feat=directlink

These show the USB thermometer, the fridge with the laptop on top (the USB cable runs from the thermometer runs from inside to the laptop) and the outlet with the fridge and controller plugged into it.

I realize the Ranco controller might be easier/more efficient, I just thought this was cool and a different way of doing things.

Also, I am going to look into not using the heating pad and just let the inefficiency of the fridge's insulation warm the fridge back up.

Where did you find the software code?

It was in the August 2010 issue of Linux Journal. I've tried searching for the article but at linuxjournal.com you have to pay something around $5 for an electronic version of the magazine.

Sounds like a cool project..do you happen to have link to the Linux Journal article?

are you taping the temperature probe to the side of your carboy?

This is the link to the online version, but you have to pay $5.99.

http://www.linuxjournalstore.com/categories/issue-196

I hadn't thought about where I was keeping the probe. Would it make a difference if it was taped to the side or just resting next to it?

GatorBeer said:

This is the link to the online version, but you have to pay $5.99.

http://www.linuxjournalstore.com/categories/issue-196

Click to expand...

I don’t want the whole issue.

My suggestion is to not use the X10 stuff; most of it is crap. In particular, you'd be relying on the relay units, which are pretty bad; In my experience they often miss an "on" or "off" command, which could be very negative for your application. I prefer the Insteon stuff from Smarthome for home automation, but I'm not sure it their SDK is public.

I also think that it would be much cheaper and easier to get a Love controller to use; I have two of them, one on my kegerator (converted freezer) and one on the refrigerator I use for a fermentation chamber.

Like I said above, I agree that it is probably easier/cheaper/safer/more efficient to buy a Love or Ranco controller, this just seems like more fun and gave me a great DIY project.

GatorBeer said:

Like I said above, I agree that it is probably easier/cheaper/safer/more efficient to buy a Love or Ranco controller, this just seems like more fun and gave me a great DIY project.

Click to expand...

In addition your version has more flexability. You should be able to program in some alarms if things go wrong. Perhaps you could send your self an email that would indicate temp too high or too low. Or maybe a text to your phone.

You can also post your temp to a website so you can constantly monitor the system. You might even be able to turn things on and off from a website. :rockin:

Just my 2 cents.

Sean

basfords said:

In addition your version has more flexability. You should be able to program in some alarms if things go wrong. Perhaps you could send your self an email that would indicate temp too high or too low. Or maybe a text to your phone.

You can also post your temp to a website so you can constantly monitor the system. You might even be able to turn things on and off from a website. :rockin:

Just my 2 cents.

Sean

Click to expand...

This is the only advantage you have over the simplicity and reliability of using a Ranco controller.

King of Cascade said:

This is the only advantage you have over the simplicity and reliability of using a Ranco controller.

Click to expand...

Agreed... and the monitoring aspect is rather easy to do with an Arduino, ethernet shield, and a few temperature sensors.