Over the last month or two I've radically changed my approach to the brewing machine and its development. I ripped up most of the solid pipe and have been hacking different configurations with hose and miscellaneous bits so that I can test changes and fine-tune before I really commit myself.

Chilling issues

One example of testing in place is the process of cooling the wort from the boil kettle. I've had a plate chiller for a couple of years but I've not been happy with its performance. Even as we approach mid-winter the best I can hope for with a single pass and normal mains water as coolant is for 30 C wort into the fermenter.

The brew day before last I tried pumping ice water from the ice bank through the chiller as wort made a single pass into the fermenter. Balancing both flow rates the best I could manage was 25C wort. About 2/3rds through I had to abandon the test because all the ice had melted from the bank. Back to mains water as coolant and then a further problem. The ice bank was needed to cool my cellar box, and with 42 litres of wort at 25C it no longer had the capacity to cool that down to lager temps.

Time for another test. While brewing on Monday I did the Jamil trick of pumping wort around the kettle (in my case via the external plate chiller) until the wort dropped to 30 C. I then substituted the mains water for water from my ice bank. It was lovely to watch the wort slowly but surely drop to 8 C and be able to pitch instantly onto my yeast slurry.

One issue with this is that the chilling process took forever. I was able to minimise water use though, so there are some trade-offs. What I intend to do next is an idea that came from a local micro. There they use a two stage chilling process. Part A via one chiller is done using domestic cold water; part B via a second chiller is done using glycol (or the ice bank in my case). So the inefficient plate chiller will do for part B, but now I need to buy an efficient plate chiller.

Changing the wort flow path

Because I haven't done this kind of chilling before, I had not really considered the chilling path (the loop out of and back into the kettle). In my current system it goes through the heat exchange coil which I'm not happy about. While I've done some serious PBW cleaning of that coil I'm not convinced it is really sanitary. I will re-plumb the system again to eliminate this as an issue.

Better filtering

Also I need to do a better job at keeping hop debris out of the plate chiller. Some improved filtering on the kettle out and the addition of a proper whirlpool paddle should improve things greatly.

Automated brewing

All these tweaks and changes are heading me towards some serious re-building towards an automated machine. I've been slowly working on the electronics based around the BrewTroller. I've also been busy doing coding for the BT guys to allow remote monitoring and eventually remote control of a BT.

Last week I took the plunge and ordered some valve solenoids from China so things are moving here. I've also had critical eyes on the current setup, particularly with fittings that I'm not happy with and taking the trouble to source the right adaptors that I might need. When HERMAN was first built I did not have suppliers of nice shiny bits at my finger tips, so now is the time to really do this job properly. I'm about to put in a serious order with Beerbelly.

And to top off my spending spree I ordered a couple of zero-crossing solid state relays from Oatley.

Even though it has been ages since my last blog entry I've been busy building and inventing. One of the things that has taken my attention is putting together a BrewTroller control panel.

There is more information at the BT forum here.