Raspberry Pi – Bespoke heating controller project #1

I’ve been keeping an eye on the Raspberry Pi for a while now.

What’s a Raspberry Pi?
The Raspberry Pi is a credit-card sized computer that plugs into your TV and a keyboard. It’s a capable little PC which can be used for many of the things that your desktop PC does, like spreadsheets, word-processing and games. It also plays high-definition video. We want to see it being used by kids all over the world to learn programming

As someone with a history of fiddling with computers since the ZX81 in the early 1980’s the Pi held an immediate appeal for me. Additionally, something at the barn that has always frustrated me is the disjointed nature of the heating system – The inputs; a multi-fuel stove & solar thermal hot water panels, are not well coupled to the outputs; underfloor heating (UFH) and upstairs radiators. The water in the thermal store is heated and is either vented to an upstairs radiator if it exceeds a predefined temperature or preferably to the UFH or radiators by pushing up the required temperature on the in room thermostats to a level above the current room temperature. I want to add a little more ‘intelligence’ to the system – if there’s a tank full of reasonably hot water then dump it into the UFH if it’s cold downstairs or switch off the UFH if the water temperature is too low in comparison to the room temperature and so on.

The Pi, as a small low-cost, low power computer, using the kind of software I’m comfortable with may be just the ‘brain’ this system requires. I just need to learn some electronics.

The Pi has only recently been launched, trending on Twitter more strongly than Lady Gaga at one time! So I thought I’d mention my idea to the people from Pi

@Raspberry_Pi got an idea to use a R_Pi as a controller for my complex heating system – now just need to a) get a Pi & b) learn electronics!
Mar 08, 4:39 PM viaTwitter for Android

To which @Raspberry_Pi replied:

@barnconversion Have you visited our forums? If you post in the projects section, we’d love to help you get started.
Mar 08, 4:41 PM viaweb

So off I went to the forum and discovered several useful threads…

1-wire sensors for heating control
Smart home energy monitor

Those gave me plenty of areas for further research…

  • 1-wire
  • I2C connector
  • DS9490R USB adaptor for 1 wire
  • GPIO-based 1-wire driver in the kernel
  • LinkUSB device
  • I2C bridges attached to the Pi’s I2C interface
  • http://openenergymonitor.org/emon/ – Nanodes
  • Central Heating / Water controller … hardware interfacing using GPIO pins

Looks like I’ve got my hands full. Plenty to research. Lucky that there’s such a long waiting list to get your hands on a Pi – plenty of time for homework.






Leave a Reply

Your email address will not be published. Required fields are marked *