I use a Norcal/Jaybird false bottom in my HERMS system's 20 gallon mash tun and I always pull grain through it during sparging.
During mash, I recirc continuously at about 2 liters/minute and it takes about 30+ minutes for the wort to clear. 45 minutes into the mash, I raise the HLT temp to 168 and continue to recirc for another 15 minutes. I'm pretty sure at this point there are no grain bits coming out of the MT (I can see through the silicone hose at the MT outlet). To sparge, I pump the HLT water through the coil and into the MT and the wort to the BK. Both are set to about 1 liter/minute at this point. This is where there's always a problem. Grain chunks (lots of them) get pulled through the MT and end up in the BK. On top of that, the grain chunks clog the MT's pump ball valve, stopping flow. To regain flow, I have to open the valve to let the grain through and then close it to where it was before to maintain a flow of 1 liter/minute. This happens dozens of times during the sparge. It is easily the most frustrating part of the brew day. Yesterday I was able to sparge into a large 300 micron mesh filter to catch the grain chunks. I collected a lot of chunks. I'm worried that smaller grain bits got through the filter, though. The wort was certainly not clear, but this was my first time using oats, so I don't know if that has something to do with the cloudy wort.
What is going on here? I know it doesn't have to do with crush because I mill at 0.054" and the crush looks good. The grain chunks that pass through the FB are large.
This is the MT/FB I'm using:
https://www.homebrewtalk.com/showpost.php?p=6328621&postcount=177
During mash, I recirc continuously at about 2 liters/minute and it takes about 30+ minutes for the wort to clear. 45 minutes into the mash, I raise the HLT temp to 168 and continue to recirc for another 15 minutes. I'm pretty sure at this point there are no grain bits coming out of the MT (I can see through the silicone hose at the MT outlet). To sparge, I pump the HLT water through the coil and into the MT and the wort to the BK. Both are set to about 1 liter/minute at this point. This is where there's always a problem. Grain chunks (lots of them) get pulled through the MT and end up in the BK. On top of that, the grain chunks clog the MT's pump ball valve, stopping flow. To regain flow, I have to open the valve to let the grain through and then close it to where it was before to maintain a flow of 1 liter/minute. This happens dozens of times during the sparge. It is easily the most frustrating part of the brew day. Yesterday I was able to sparge into a large 300 micron mesh filter to catch the grain chunks. I collected a lot of chunks. I'm worried that smaller grain bits got through the filter, though. The wort was certainly not clear, but this was my first time using oats, so I don't know if that has something to do with the cloudy wort.
What is going on here? I know it doesn't have to do with crush because I mill at 0.054" and the crush looks good. The grain chunks that pass through the FB are large.
This is the MT/FB I'm using:
https://www.homebrewtalk.com/showpost.php?p=6328621&postcount=177