Brewzilla 35L grain going through the pump

[Xodaru]

Hi,

I'd like some advise to work out where I keep going wrong. I have a brewzilla 35L that I've used twice now and both times I've ended up with grain getting into the pump system. Apologies on the lengthy post, I've included as much detail about my experience as I can.

The first time I was making a Wildfire IPA. After 3/4 of the grain was put into the malt tube the texture was miles too thick, so I ended up having to add an extra 5L on top of the 20L of 67degree water in there. I was careful not to overfill it, or get grain down the center tube.
Once the mash started I noticed that the level was rising I guess faster than it was exiting the mash tube, so after a minute I turned the pump off to prevent an overflow. I kept this process up for 15minutes and then grain started coming out of the recirculated liquid and blocked, pump shut off. I managed to take over manually for the whole mash cycle and saved the wort which has almost finished fermenting quite nicely yay!

When i cleaned everything out I noticed (to my surprise) that there was no grain at all in the bottom of the brewzilla unit. The grain was getting in the bit of stainless pipe that brings the recirculated water back to the top, it was packed with grain.

After a lot of back and forward talking to kegland we believe that it was my mixing in the grain when I was entering it into the malt pipe that caused the bottom to move a bit allowing some grain to get out of the pipe. I guess the false bottom does jack to stop grain in that situation. They suggested I could try BIAB and I ended up purchasing the one recommended.

Second attempt, today. I wanted to give this recipe a try https://beersmithrecipes.com/viewrecipe/2598136/jedi-juice-01-clone
I put the bag in the malt pipe and made sure it was secured well. The water to grain ratio this time was great so things were looking better.
During mash, the level rose again but much faster so I stopped the pump well before it overflowed.
It took much longer to go down this time, and when I turned the pump on again - grain and blockage shortly after.
I couldn't save the wort this time around because it seems the bag was badly impacting the drainage, I could get no decent circulation happening and the temp kept dropping.
So, obviously I thought there must of been a hole in the bag. But to my annoyance, no hole whatsoever in the bag. A little bit of grain particles on the outside, but that's all. And again, at the bottom of the unit there was no grain to be found either.
It was again all in that side pipe.

I feel stupid, what am I doing wrong? I've watched so many videos on youtube with how people use the brewzilla and I'm just not getting the same results. I figured a bag would make things better but in fact made it worse. I thought I was being way more careful the second time around too.

 

[MHB]

Sounds like the crush on the grain might be worth a look. For a recirculating system the grain wants to be just opened up - not powdered.
Mark

 

[ABG]

As @MHB has said, check your crush. I've only ever had issues once with grain causing problems with either a R35 or B65 and that was because the level of the water in the mash was over the top of the pipe (my miscalculation). To strop stray pieces of grain getting into your pump, chuck a hop bazooka on the end of your return pipe, or put a tea strainer over the top of it as David Heath does in his Youtube vids.

 

[Xodaru]

Thanks for your replies!
The second time around the grain was finer than it was the first time. The second time also did not have the return pipe connected due to the bag.

Would the grain crush being finer be why the water was not flowing out of the bag and malt pipe very well? Should I abandon using a bag with the brewzilla altogether? Both times the mash level rose, second time much quicker than the first though. I don't see this happening in other videos either.

 

[tramsjoe]

Perhaps when you're turning off the pump it's sucking up grain from the malt pipe? It's quite a common problem i hear

Also if you mill your own grain, try conditioning it first. Ive never had a stuck mash or sparge and have always conditioned the grain first.

 

[Xodaru]

With the bag I would have thought this is impossible. How do you condition the grain? First time I milled it myself, second time my local home brew store did for me.

 

[Reg Holt]

As tramsjoe says it has been covered before about grain being sucked back up the pipe when turning off the pump, grain crush in my Guten is quite fine, small particles go through the system and dumped on the top of the grain bed. I am also stumped as to why you were told to use a bag.
Guten or Brewzilla there is really no difference performance wise and any larger particles should not be getting through. Reading through again I think that you have the return tap fully open.

 

[Xodaru]

Ah i just realized what was meant by the back up the pipe comment. That's interesting, and would explain why I never find any grain outside of the malt pipe.
Assuming the best solution is to actually avoid turning it off to start with - what can i do to reduce the rising mash?

The return tap being the blue tap? If so then yep its fully open when the pump is running - is that a no no?

 

[The Mack]

-Rice hulls into the grain bill
-Don't have the pump on when mashing in- just stir it yourself and take your time
-When turning the pump on, just crack it a little bit and monitor the wort level, it doesn't need to be flowing at 100km/hr through the grain bed
-Do you run the top screen?

 

[Xodaru]

Thanks so much guys. Found another video on youtube that talked about the grain getting sucked back up the pipe and how to control the pump speed. Both those things I didn't realize and I'm sure that's the cause of both my attempts. Everything is starting to make sense now phew...
I didn't use the top screen on both attempts, from what I understand it's not really required. Should I be using it?

Next attempt, I won't be using a bag for sure!

 

[The Mack]

Maybe not required but doesn't hurt- I can't see any reason why they would negatively affect a brew day, so I like to use them.

Also, I put that little black rubber thing over the overflow pipe when mashing in so no grain accidentally falls down it- taking it off once all grain is added.

 

[fdsaasdf]

Isn't the point of the top screen to ensure there is a barrier between the grain bed and any of the areas where grain could cause an issue... like the wort return?

 

[ABG]

@Xodaru it sounds like you've got the outlet from your pump running flat out. You'll need to throttle it down by adjusting the ball valve to the point that the flow out the pump more or less matches the flow through the grain bed.

If you don't use the top screen, you'll need to take care that grain isn't going back down the centre return tube. I do this by popping a hop bazooka over the top of the tube which filters grain particles and stops them falling through. Perhaps watching a video from David Heath or The Brewing Network on Ewechube may help you get a better idea of what to look out for. Better still, join a local brew club and brew with someone experienced.

Good luck mate. You'll get it sorted.

 

[Xodaru]

Yeah I did for sure. Did not realize that, lesson learnt there
Interestingly I've watched many of the brewing network ones, quite like watching Gash brew. I always skipped the 65L brewzilla ones he did but tonight I watched them and sure enough that's where he mentions both keeping the outlet hose out of the grain when turning the pump off and controlling the pump speed.

From now on I'll just watch everything, even if it seems irrelevant as i might still learn something.

I wouldn't have worked this out without the replies here so thanks everyone!! Really looking forward to the third times lucky next weekend!

 

[Xodaru]

Third time lucky with all the advice given here!!

No grain getting in the pump and I controlled the flow. There was still an issue with the lack of draining down through the grain even with the flow quite minimal but I improvised with a tea strainer. I think I was not nearly generous enough with the rice husks.

 

[wide eyed and legless]

Isn't the point of the top screen to ensure there is a barrier between the grain bed and any of the areas where grain could cause an issue... like the wort return?

The grain bed is the best filter, small particles going through the pump isn't an issue, I think Xodaru's problem could be the liquor to grain ratio, no need for rice husks if the mash is made more fluid.