Brewtendo Fermentation System

(resurrecting this original thread from the old forum)

Introducing the Brewtendo


The temperature and door open/closed sensors are plugged in using the original gamepad connection on the front.


The Brewtendo’s display. No need to blow on any cartridges.


Power in, Heater out, Fridge out.


This is where the magic happens.
Brains on top: Raspberry Pi, Arduino Uno, BrewPi board & screen on the upper half. The Raspberry Pi’s OS runs on a USB 3.0 stick.


Now You’re Brewing with Power
High-voltage plumbing on bottom: power coming in, split using a terminal block, going to:

  • an iPad charger to power the Raspberry Pi
  • hot going to the the two SSRs
  • neutral going to the wall socket
  • everything grounded
    Bottom also contains the wires coming in from the temp sensors, and the USB hub. Connected to the USB hub: WiFi dongle, and USB cable going to the Arduino Uno.

Back Story:
I thought that the NES would make an awesome project box. So I got a cheap, non-working unit on eBay, and ripped out all of the guts (Now I could never be sure, but I thought that I heard the sound of Taps being played. Gently.). It took some Dremeling to get some of the old screw mounts out of the way, but it turned out to fit everything snugly. I also used a Dremel with a plastic bit and the drywall adapter to cut out the two holes in the back for the outlet plugs. That’s really the only modifications it needed. 3M double-sided sticky foam/tape secures everything in place, which was a suggestion I found on this forum (thanks!). The only exception is the Raspberry Pi, which is held in place with Velcro, as I know from experience that I’ll be pulling that thing in and out as the SD card becomes corrupted from time to time.

Future Improvements:

  • LED: Turn the LED blue when cooling and red when heating
  • Buttons: the Power button should switch on/off everything, and the Reset button should, for example, send a “sudo shutdown -h now” (or some equivalent shutdown signal) to the Raspberry Pi, to prepare it for shutdown (to prevent corrupting the SD card when yanking the power).
  • Gamepad controller: the second controller port should allow plugging a stock Nintendo controller, select button toggles through beer/fridge/profile modes, and up/down buttons would increase/decrease the target temperature.

Thank You’s:
Major, major props to Elco, for many things - not the least of which:

  • Not skimping on the SSRs. These things are tanks. Plus they came with plastic shields to protect from arcing - this would have been a seriously unsafe project without those.
  • Going with pluggable connections. Had the screw terminals been hard-wired to the board, assembly would not have been as simple as it turned out.
  • Providing updates and answering questions on the forum like a madman. You rock.

Also, a huge, huge thanks to all of you guys on the forums. I was able to avoid so much trouble with this project because you guys took the trouble to document the snags and successes you ran into along the way. Plus, this build was heavily inspired by the “show your build” thread. If I ever meet any one of you guys in person, I owe ya a beer on me.

(Note: this project was built long ago, using the original Arduino shield version of brewpi)

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