BrewPi

[BrewMasterBrad]

So I took the plunge and setup a BrewPi to control the fermentation temp in the kegerator in my office. If you have not heard BrewPi, Google it. So far, I am very happy with the results. It maintains my fermentation temp with about .1 degree Celsius. This is on a lager, so I will be interested to see how it does on a much more active ale fermentation. After adding up all the equipment and parts, it was not cheap. I am going to build a second system for the chest freezer in the garage, but I am going to use an old laptop running Linux rather than the Raspberry Pi and I am also not going to buy the BrewPi shield for the Arduino and instead I am going to wire up my own system. This should keep the cost down and it will be fun to play around with wiring the electronics.

Has anyone else used the BrewPi yet?

[brahn]

So, for the BrewPi you need a Raspberry Pi, Arduino, plus the BrewPi arduino shield?

By the time you've bought the BrewPi case, you could just about purchase a BCS-460 that would be able to control both your kegerator and freezer (if you could run wires between the two). I may be biased on this one.

It's a neat project either way, I'm glad to hear it's working well.

What do you plan on using to control the relays on the old laptop? Are you still going to use an Arduino for the GPIO pins? You could probably get by with just a Raspberry Pi, I don't really see why the Arduino is necessary.

[JonW]

Have to agree with Brent on the BCS-460.... but then, you already knew that.


If you are maintaining temperature within .1 degree, you are likely short cycling your compressor a lot. Expect it to go out soon.

[BrewMasterBrad]

The relationship is somewhat symbiotic between the Arduino and the RPi. The RPi runs Raspbian Wheezy which provides the logging and the web interface. The Arduino actually runs the PID algorithm and controls the relays. If the RPi stops working, the Arduino continues to control the temperature, but the logging functions are lost. It is admittedly overkill since either device could probably do the job independently, but using both devices provides stability and additional features.

The final cost of the BrewPi setup was probably just under the cost of a BCS-460 by itself. In addition to the BCS, I would also have to purchase temp sensors and relays which would push the price close to $200. The advantage of the BCS is that it can control more than one device right out of the box. The BrewPi can control multiple devices as well, but you would have to get an additional Arduino and install another instance of BrewPi on the Raspberry Pi for each controlled device.

Hopefully, I can do a side by side comparison of the two systems and do a write up on all the fun.