Immersion Chiller
Home made immersion chiller
This is my home made immersion chiller which I use for cooling the wort. These can be bought in some homebrew shops at quite a reasonable price, but it's often more satisfying to use equipment which you've made yourself.
Cooling the wort quickly is important because it helps to produce the 'cold break' which precipitates out proteins which can cause haze in your beer - and it also means that you can pitch the yeast quickly, lessening the chances of the beer getting infected by wild yeasts and bacteria. This chiller will cool 5 gallons (23 litres) down to 25°C in about 30 to 40 minutes, depending on the temperature of the cold water going into it.
It's made from a 10m coil of 10mm copper tube - sold in DIY shops as 'microbore copper tube' - using no specialist tools apart from a tube cutter and a blowlamp for soldering the joints. Two short lengths were first cut off the coil, straightened and then the ends carefully bent by hand so that the ends (where the water comes in and goes out) will be outside the bucket. This is in case of accidental leaks - you don't want water in your beer! Starting at one end, the coil, which was originally about 20 inches (50cm) in diameter, was gradually tightened around an old demijohn so that it ended up about 8 inches (20cm) in diameter. Two 90° elbows were used to attach the coil to the two uprights, although if you have pipe bending equipment you could probably do without these.
What you end up with can be a bit like a 'slinky spring' so I have soldered two straps from top to bottom (made from some old flattened copper tube) to hold it together a bit more neatly - but it's not really necessary.
Plastic tube is used to connect to my cold water tap (cold water goes in at the top of the coil) and the hot water that comes out is collected in an old fermentation bucket which I then use for cleaning my equipment. [with the cost of water in the South West of England, it's important to save every bit that you can!]
For efficient cooling, it is important to keep stirring the wort - and in the summer, I often find it necessary to use a minature cooling coil between the cold tap and the chiller to chill the cold water going in as well. This minature coil is placed in a large bowl of iced water, and the cold water runs through it before it gets to the chiller to cool the water down.