Counterflow Chiller – The Making Of (ULCBP)

March 21, 2011

When John heard about the Ultra Low Cost Brewery Project he was more than a little excited.  Not only did he want to get involved and make some tasty brews, but he kindly wanted to make a contribution.  One thing the project doesn’t have is a wort chiller, so he took it upon himself to knock one up.

What is the point of a chiller?  It sits between the boiling kettle and the fermenter and allows you to rapidly chill the wort post-boil.  This locks in the aromatic oils of the hops.  It also means that the wort doesn’t cool slowly, so it doesn’t sit at the infection temperature for extended periods of time.  These are both good things.

There are a few approaches for chillers.  By far the most common is simply a copper coil that is lowered into the kettle and water is pumped through – known as an immersion chiller.  This approach wins out for its lack of complexity and low cost, but it doesn’t cool the wort exceptionally quickly and it doesn’t allow for some advanced brewing techniques (such as a hop-back).

The other type is inline chillers – which are essentially heat exchangers that sit between the kettle and the destination vessel and chill small quantities of wort very quickly as they leave the kettle.  We settled on the counterflow chiller (CFC) design where you have an small inner tube carrying wort surrounded by a larger outer tube carrying water in the opposite direction (hence counterflow).

You can do this with some small diameter copper tubing and a garden hose outer, but being a man to do things correctly John opted on a full copper CFC.  The tubing he used was airconditioning pipe and the first mission was to feed 7.5m of small tubing inside a larger one.  Plenty of washing-up liquid, water and patience required!

At times this required a little loving tap with a hammer – but be careful because this annealed pipe kinks very easily.  Make sure you thoroughly deburr the pipes before you start – you don’t want to make life any harder than it already is!

Next step was to neaten things up a little and roll the whole lot up around an appropriate form.  We chose a keg, as a bend radius any smaller than 13″ will cause kinking.

Next you have to make the whole think water-tight.  John found some reducing T-adaptors.  You will need to file out the ridge so that the small pipe can pass all the way through the T.  This is a tedious task, but resist the temptation to reach for the dremel – a round file proved (yet again!) far faster.  Then it’s time to crack out your soldering skills and make it all permanent.

Below is the finished product.  Quick fittings for garden hose is a good idea.  The vinyl lines for wort in and out I am yet to be convinced about – this liquid is going to be hot!  But it all needs a trial run, and no-doubt some refinement will ensue.

Advertisements

Gem Scale (ULCBP)

March 18, 2011

Thanks to a sneaky $10 Ebay purchase hopefully the ULCBP is going to usher in a new era of accuracy, reliability and repeatability.

The first brew that came out of the ULCBP was an English bitter – ended up being a most phenomenally bitter bitter!  Clearly the ‘handful’ measurement of Super Alpha bittering hops leaves something to be desired.

The second brew to come out of the Project is a lovely roasted stout.  I’m very pleased with this one, but can I recreate it or improve on it?  No – none of the hops additions were measured with any sort of accuracy.

This I see as a huge problem.  If the Project is to produce beer recipes that can be remade and improved upon, I need far better control over what is actually going in.  I’m pleased with the measurements going on at all other stages in the process, but I have not had the capacity to reliably measure out small quantities of hops (say in the 15-50 gram range).

Until now that is.

Combine this with a nice new brew journal, and tasty beers await!


Star San (ULCBP)

March 18, 2011

The latest goodie has arrived for the ULCBP, not a necessity but something that promises to make life much easier.  Star San.

This foaming sanitiser from Five Star Chemicals cleans on contact, even just with the foam.  You need very little of it to get the job done (30mL/5L) , so a $20 half-Litre bottle lasts a good while.  But the best news is that it is a no rinse sanitiser, meaning that unlike other options you don’t have to spend time rinsing and rinsing.

Until now I have been using household bleach at a ratio of 150mL/20L.  The amount of rinsing that I have to do to get the bleach smell out of the fermenter is quite a lot – and a fermenter not being a small thing, the amount of weight having to shake around to do it is unpleasant on my back!

The plan is that Star San will turn this into an easy 5min operation.  Dose, shake, pour out, brew on!

I think I’ll still go with bleach in the laundry sink for bottle cleaning however.  It only seems to take one sink full of fresh water to rinse them of any bleach odour – possibly this discrepancy exists because the bottles are all glass and the fermenter is plastic.  Either way, the bottle process I can live with for the time being.


Digital Thermostat (ULCBP)

March 3, 2011

The primary purpose of the fridge is to maintain the perfect brew temperature during fermentation.  For ales this is around the 18C mark.  Sure, fridges come with their own temperature control but you’re never going to see anything about ~6C.  So you need some sort of additional control mechanism to achieve the temperature ranges we want to play with.

The solution is a thermostat that sits between the fridge and the power socket that turns the fridge on and off in response to a temperature probe that sits inside the fridge.  You can buy such controllers from homebrew shops – but you can also easily assemble your own for a fraction of the price.

The device that I found on ebay is advertised as an aquarium controller.  I don’t think it actually is – it’s just a generic industrial controller – the STC-1000, for what it’s worth.

This device is has two switching circuits, one for cooling and one for heating, meaning that you can use it in conjunction with a heating pad for a wide variety of tasks and all throughout the year.

The connections on the back are simply screw-down terminals so you’ll need an extension cord (or two if you want both heating and cooling circuits), some terminal strip, cable ties and an appropriate electrically safe container to mount it in.

Spend for my thermostat: $40

Retail thermostat: $120

Spend so far: $195

Savings so far: $1660


Kettle Pick-Up and Tap Extension (ULCBP)

March 3, 2011

Brew Day was an excellent test run for the ULCBP hardware.  One problem that was identified was the fact that the high position of the tap (necessitated by the curved bottom of the kettle) leaves a large amount of wort behind.  Around 10L!

The solution is a low pick-up tube and a tap extension that extends to below the height of the pick-up.  That way we can achieve a syphon effect and negate the high position of the tap.

(pick-up tube angled to the side to avoid slurping whirlpooled sediment)

Having tested this new arrangement now the kettle only leaves 1.8L behind – much of which will be chock full of sediment anyway.