Brewzilla BIAB no sparge efficiency problems

[SanPancho]

brewzilla brewhouse, brew'n'water, and software is brewers friend- 55% ending kettle efficiency. ouch. has happened multiple times recently. thought i wasnt crushing my wheat or rye, which are in alot of my beers. but after getting a separate mill for .020 milling of those, no change. main mill is set at roughly .030 recently. typically shoot for 5.4pH. 7.25 gals of water, yesterday was 12# of grain- 7 base, 2 wheat, 2 vienna, 1 carafoam.

did 25min at 146ish, then 20 at 157ish, then 10 min mashout. pre boil gravity was only 1036/1037. i had about 6.25 gals after squeezing the **** out of the bag. after boiling down to just under 6gals, i'm at like 1038/1039 OG. ugh.

i had recirc going pretty slow. maybe too slow?
i slowly lower bag into brewzilla, hard to believe it could be dough balls.
double crush? take the main mill down to like .025 ?

the reason im frustrated, is that i used to get like 65-70%. besides mill settings, i dont recall any real difference in process. maybe i'm doing recirc too slow? i honestly cant think of where this came from. i know grain is cheap. but i'd prefer to figure out why i've dropped roughly 10%. becomes pain in the ass to run old recipes as i cant rely on them.

 

[Zadkiel]

perhaps you could make a list of possible reasons and then do tests to eliminate them - could it be your mill or grain, try buying a recipe of grain crushed and see if the efficiency goes up. Could it be temps, use a second thermometer to check the brewzilla temp against. Use a known weight to check your scales? that sort of thing.

 

[Yooper]

One thing I've noticed with step mashing in the Brewzilla is it takes a LONG time to raise the temperature. I'm using the 240 gen 4, but even so....so I don't step mash anymore. The pump is anemic, even at full throttle, so recirculation is not all that great and the temperature at the bottom when I boil is 219F (which it's not, I know). I accept those limitations, but as an example today I got 100% conversion efficiency according to the software; 80% preboil, and see the rest below:

This has been the pattern over the last at least 8 or so brews, and I use a bag for mashing. I think several things are going on here. First, the temperature between the RAPT probe near the top and the temperature at the bottom is WAY off. My wort does not boil at 218, more like 211. So it's heating quite a bit more at the bottom where the pump is.
Secondly a full volume mash is always giving me less efficiency than a mash/sparge- usually not a lot, but enough to notice.
I've decide to just accept it, as it's 'only' about 8% loss compared to not having the Brewzilla. Recirculation, not recirculation, fast, or slow, etc- doesn't seem to matter.
I know it doesn't answer your issue, but I wanted you to know that it's not just you! It's just not going to seem to give us the efficiency we had in our older traditional systems I guess.