Temperature control

When you first start brewing there are a bunch of different toys to spend your money on. There are shiny things, electric things, glass things, things with pipes everywhere and big steam-punk dials. It’s very hard to know what to go for next!

Here’s my recommendation: buy a temperature controller that you can use with an old fridge to make yourself a controlled fermentation chamber. It’ll do amazing things to your beer. More than any giant pots or clever cooling systems. By fermenting your beer at the right temperature for the yeast you can avoid off flavours and characteristics that are incorrect for the style or, in some cases, just plain nasty. You beer will taste ‘cleaner’ and less like home brew 🙂 You can also cold-crash (dump the temperature quickly down to near freezing) to drop yeast and other haze causing particles out of suspension. This means super clear beer—especially if you use gelatine.

My set-up is an old fridge that I purchased from trade-me. It cost about $30 and was in perfect working condition. Every now and then someone gives away an unwanted fridge too 🙂

stc-1000The fridge is plugged into a device beloved of brewers all around the world. I speak of the venerable STC-1000. This is a very simple (and very cheap) little temperature controller that can be purchased from eBay or AliExpress for about NZ$30. It has two relays and a temperature probe. You set the temperature at which you would like to keep your fermenting wort, then the STC-1000 will switch either the heating relay to warm things up or the cooling relay to cool things down and keep your precious beer at the temperature you specified. You have to wire it up, but there is a lot of very good info online to assist with that. If you don’t feel comfortable then find a mate who knows what they’re doing and swap their knowledge for some beers.

My STC-1000, running the fridge, keeping my beer happy

Here’s how I put mine together:

The Parts:

  1. An STC-1000
    I recommend buying one from these guys. There are several versions of logic board, and the one sold there is able to be upgraded with new firmware which turns this little device into something that will kick the pants off temp controllers that cost $100–$200 more. If you’re handy & aren’t scared of Arduinos, wires and opening up your STC-1000, then you can upgrade it easily to do a variety of new tasks.
  2. A project box or case
    I used one of these from Jaycar. It looks good, but the aluminium was hard to cut. I think I’d use a plastic one next time.
  3. A double power socket
    This is where things start to get a little tricky. A standard double wall socket is designed for power to be fed in and distributed to both sockets at once. The sockets on the back of  your temp control unit will need to able to be switched on and off by the STC-1000 independently of each other. You can modify standard wall sockets to do this, but there is a product available in NZ which is a wall socket with two independent sides. It’s designed for installed devices in your kitchen such as a waste disposal unit and a dishwasher where the switch might be on the bench, but the plug under the bench. I found one at an electrical supplies store. It’s a PDL 693/2 and it is perfect for this application. The other alternative is to buy an enclosure big enough to install two standard single plug sockets.
  4. Some 240v connector blocks
    These are the big meaty ones. You’re going to be moving 240v around inside your temp controller and you want to make sure your components will take the load. These guys here will do famously.
  5. An old extension cord or computer cable
    I used an old “jug cord” style computer plug. I have a lot of them lying around. I cut off the end that plugs into the computer, then another 15cm or so of the cord so I could use the wires to join everything together. The remaining cord (the end that goes into the wall, plus the long bit I hadn’t cut) became my power cord.

I used these instructions for wiring it up. It worked perfectly. I have no idea if it was legal for me to do that, and if you decide to give it a go yourself please don’t do it just because some guy on the internet told you to. Those instructions worked for me, but your milage may vary.

hot-coldSo now you have a working STC-1000 controlling two power outlets. Plug the fridge into one side, and some kind of heating into the other side. There are lots of options for heating. Some people use those brew belts, or an old hair dryer. I use an old halogen desk lamp. You just want to be able to gently heat your wort should the temperature fall below your set point.