I brewed my first 20 gallon batch on a brand new system yesterday and experienced a stuck sparge (fly sparge). There was no non barley grain used. I milled the grain on the same mill at the LHBS I always use. I'm pretty sure I opened the valve too much and created a suction that compacted the grain bed, I was pressed for time and did the entire sparge in 45 minutes. I had to resort to stirring the grain bed and even put a pizza pan on top of it and pressed out as much as I could. There was still a significant amount of wort left in the tun when I dumped it.
My question is this: If I shoot for a 45-60 minute sparge on my 5 gallon system, do I need to multiply that time by 4 for the 20 gallon system? I'm using a 26 gallon stainless tun with a false bottom. I had 52.5 lbs of grain and about 12 gallons of water and 10 gallons of sparge water, all at about 165*F.
My question is this: If I shoot for a 45-60 minute sparge on my 5 gallon system, do I need to multiply that time by 4 for the 20 gallon system? I'm using a 26 gallon stainless tun with a false bottom. I had 52.5 lbs of grain and about 12 gallons of water and 10 gallons of sparge water, all at about 165*F.