Computer Controlled Beer Fridge

[conradneilands]

For those interested in getting an old computer to do something useful on the cheap, I have put together some equipment that can control the temperature of my very old beer fridge. It's all been working happily for the last 6 months now.

All the code and equipment used and a pretty graph of whats happening right now:
http://temperature.gotdns.org/

I have an Relay Board, RS232 thermometer, 80cm computer fan (To circulate air in the fridge), Optional heater pad

I have made the temperature falls and rises very gentle as the fridge is pretty harsh if l use a fridge mate, I also tend to have a lot of conditioning bottles in there, so I don't like to stress them too much

All the code is free to use, just don't blame me if something doesn't go to plan

 

[Wolfy]

Sounds and looks cool.

However, given that the costs outlined on your webpage are a fair bit higher than a Craftbrewer Tempmate or the Mini Digital Temperature Controller's on Ebay, what advantage does your old PC temperature control method have?
I presume it plots and logs the temperature, which the others cannot do - which is nice, but are there other advantages too?

 

[conradneilands]

Yes its not really going to save you money and there is a fair amount of expertise involved to make it work, so yeah i'm not trying to sell it to anyone nor encourage anyone, but If you were thinking about it, it may give you a few hints about what can work.

The reason I made it was as a bit of fun and to remove some frustrations I was having with other controllers.
I personally tried a few different ones and got sick of them overshooting the desired temperatures by several degrees. And worse still totally stuffing up my brews. My crappy old fridge also seems to have one setting: deep freeze.

I was also after some automation for dropping or raising the temperature at set rates, ie I can tell it to drop the temperature as little as 0.1 degree every hour. I used it last winter to do a very controlled lagering and crash cool which gave me one of my best brews ever

Sounds and looks cool.

However, given that the costs outlined on your webpage are a fair bit higher than a Craftbrewer Tempmate or the Mini Digital Temperature Controller's on Ebay, what advantage does your old PC temperature control method have?
I presume it plots and logs the temperature, which the others cannot do - which is nice, but are there other advantages too?

 

[Ducatiboy stu]

Will this install on ubuntu/debian...??

 

[zagadka]

Looks good! I like your controlled rise and fall stuff.

I've been messing with a similar project but Python/Postgres/Parallel port based (soon to be Python/Pg/RS232/PIC based) system.

I was also after some automation for dropping or raising the temperature at set rates, ie I can tell it to drop the temperature as little as 0.1 degree every hour. I used it last winter to do a very controlled lagering and crash cool which gave me one of my best brews ever

I've built in set points with date stamps on them to accomplish this - you can schedule ramp-ups and downs or steps in temperature just by adding a few records to the table. This is also rendered in the graph as the target band moving up and down.

Some Pics

Will this install on ubuntu/debian...??

Yep you will just be apt-getting instead of yum installing... The packages are listed by conradneilands on his site.

 

[Ducatiboy stu]

oops..I missed that bit on his web site.... apt-get = :icon_chickcheers:

 

[scott_penno]

Greg Lehey (groggy) has some undertaken a similar project which can be found at http://www.lemis.com/grog/brewing/temperature-control.php.

sap.

 

[Zizzle]

PHP ick!

I hacked up my solution a few years ago when I worked out that in winter on the gold coast you need a little heating AND cooling to keep even temps.

http://www.aussiehomebrewer.com/forum//ind...showtopic=10518

I ran a good length of CAT5 to the fridge so that I didn't need to run an extra PC. These days I would just load some code into an Atmega CPU and have it all self contained. Low power. Drive a $10 wifi usb stick for data reporting.

 

[conradneilands]

Will this install on ubuntu/debian...??

Probably, I originally tried Ubuntu because it to had a cut down internet installation, but for some reason ubuntu didn't like the low power via eden was using.
Its all held together with common scripting languages and cron so any distro your comfortable with

 

[Tony]

you can get a 0 - 40 deg thermostat for $30.

 

[conradneilands]

PHP ick!

I hacked up my solution a few years ago when I worked out that in winter on the gold coast you need a little heating AND cooling to keep even temps.

http://www.aussiehomebrewer.com/forum//ind...showtopic=10518

I ran a good length of CAT5 to the fridge so that I didn't need to run an extra PC. These days I would just load some code into an Atmega CPU and have it all self contained. Low power. Drive a $10 wifi usb stick for data reporting.

Is that a PHP flame? meh I was going for simple, what did you use?
I found the only time where it starts hunting was when the ambient temperature would swing above and below the desired temp on the same day, this coud be overcome by setting the heating or cooling set points a little higher than 0.1

I should point out that my temperature probe is either inside the fermenter (in a thermowell) or buried under a few bottles, so the temperature changes are naturally quite slow and predictable

The Atmega sounds like i would have to learn proprietry code, i'm interested though. If i had more time and didn't get a retired embedded pc from work i my next choice would have been an openwrt setup
I've also tried a wireless adapter there for a while, but that lots of power to be burning 24/7, so Cat5 it is

 

[Pete2501]

When I first red the title I was thinking HAL. Then I thought it would turn the fridge against you and ruin your beer.


Just what do you think you're doing, Conradneilands?

 

[Zizzle]

Yeah PHP is not up there on the list of nice programming languages in many people's books, but each to their own.

I used Python and a bit of C for mine.

The open source tool chain for Atmega chips is actually pretty good. I used it from the brewbot.

http://www.nongnu.org/avr-libc/

and one of these http://www.futurlec.com/ATMEGA_Controller.shtml

Have you heard of the Arduino? It is open source hardware and software.

I've also go one of these which was pretty cheap out of Hong Kong and runs linux:

http://www.friendlyarm.net/products/mini2440

Could do a pretty good little display on that LCD too.