I am a long-time BZ 3.1 user that moved to the Gen 4 65L as soon as it was available, and I am four batches in to learning & dialing in the new system. Here is what I have learned to date—please feel free to add to this as other best practices are developed and proved in.
My Gen 4 Tips & Best Practices So Far
- PID: use it (have to turn it on in the controller Settings), and use it with the Kegland and/or David Heath recommended settings for your batch size (see their YouTube videos and take screen shots)
- BZ Temp Readings: mine arrived reading 5.7F low vs. actual, which made my first batch in it finish fermentation at way too high of a FG! I got a simple and not expensive reference thermometer, plunked it into the middle of the malt pipe full of water (just above the bottom malt pipe plate) and calibrated it (in the controller) at 150F and 200F. The BZ Gen4 now stays within 0.5F of the reference thermometer, and my FGs are hitting Brewfather predicted values.
- Power: I use 100% power when heating up water and bringing the wort to a boil. When mashing, to include steps, I turn it down to about 40-50% power, which decreases the temp overshoot severity but does not eliminate them. A nice option when boiling is to *not* use 100%, and I find that ~65-70% power (5.5gal batch) results in a nice but not violent boil.
- Mashing Temperature Targets: do not go straight to the temp needed, but ‘walk’ up to it. For example, when mashing out at 168F, I usually put in about 166F and correct it later when close. Otherwise, it may overshoot by 2+ degrees before returning down, sometimes by a lot.
- Pump Clogging: never had a clogged pump in my 3.1 BZ, but clogged multiple times every batch with the Gen 4 UNTIL getting a BIAB bag…The Brew Bag-Designed for Brew In A Bag-This is your LAST brew bag! now has a BZ Gen 4 65L specific version for either the kettle (what I use) or to use within the mash pipe. Using this bag also made the boil and what goes into the fermentor much cleaner than before—highly recommended!
- Recirculation when Mashing: the pump’s power will exceed the strength of your grain bed. Turn up the recirc too high and you can turn your mash into a useless pile of goo…ask me how I know. Start as low as possible and gradually step it up to where you want it. However…(see next recommendation)
- Temperature stability seems highest when there is a low-ish amount of recirc, but worst with high or no recirc. I am sure the Heat Exchanger Dish will help this, but it is not out yet in the US—I am anxiously awaiting it.
- Also, you can change the pump %, but that does not change the strength the pump flows at, but rather the percentage of time it is on/off. Sorta useful, maybe.
- Grain Crush: I am using a three-roller mill (Grain Mill with 11 lb Hopper and 3 Rollers) and crushing the grains twice at the widest setting (0.065?). Any finer of a crush results in a crazy amount of grain escaping both filter plates due to the previously mentioned pump strength.
- Efficiency: in my 3.1 BZ, I usually got about 78%, sometimes higher. My first batch in the Gen 4 was 74%, and I am now hitting 76-77% with repeatability. Glucabuster used very sparingly in the mash seems to enhance efficiency by about 1-3%.
Gen4 came with a higher learning curve than Gen3 did, but also offers the greatest flexibility and customization. Using the Brew Bag last batch, and for the first time ever, I was able to clean the Gen4 while it sat on it’s SSBrewtech BrewCube (i.e. didn’t have to move it and no dumping needed), which was a lovely improvement. All in all, it’s a keeper, but I am hoping sharing best practices lowers everyone else’s learning curves. YMMV.