Automated home brewing

The office conversation this lunchtime went a bit like this:

Me: “Two beer posts in a week is too much, isn’t it.”
Ben: “Maybe.”
Me: “OK. Damn shame: I’ve been sent a great automated brewing project; it’s way more complicated than the ones I’ve seen before. I’ll maybe put it up next week, after the new website goes live.”
James: “Can you send it to me now please? I’d love to read that. I want to update my system at home.”
Gordon: “Me too, please.”
Laura: “Can I see it?”
Clive: “That sounds brilliant.”
Eben: “Mmm. Beer.”
Lance: “Did someone say beer?”
Emma: “Do you have a link I can see?”

So I apologise for inflicting two posts about beer on you in three days: I promise not to mention fermentation at all next week.

Ted Hale blogs at Raspberry Pi Hobbyist, where he concentrates on physical computing with the Raspberry Pi. His most recent project brings in another of his hobbies: home brewing.

We like this not only because we like beer, but because think more Pi projects should employ propane.

We’ve seen brewing projects where a Pi controls simple heating and cooling, but here, Ted uses a Pi here to control all the parts of the brewing method called partial mash: for this he needs to be able to:

  • Open and close a valve to a tank of propane
  • Start a grill igniter to light the burner
  • Detect if the burner actually did light
  • Sense the temperature for the wort (the brew of water, malt extract, and hops)
  • Operate a pump for circulating water through the wort chiller.
Ted had problems over the build, including discovering that one of his sensors actually melted at high temperatures, finding that the igniter gave off so much electromagnetic interference that the I2C bus was unhappy. Being a seasoned hacker, he found ways around all the problems he encountered. The following paragraph, describing how he dealt with the interference, demonstrates why we think Ted is so great:
I used shielded audio cables commonly used for microphones.  I am also a musician so I had some of this already.  If you have to buy a small reel you may find that it is rather expensive.  Cat-5 cable may also work well.  That is what I use for my hot tub controller, but it is not subjected to the massive EMI of this system.
This guy is a musician with a hot tub who brews his own beer and hacks with the Pi for fun. We are in awe.

There’s a writeup over at Raspberry Pi Hobbyist about how the whole setup comes together, and James, I expect you to have overhauled your entire home system over the weekend.