So, I decided to make a small change in my process, and I am at a complete loss to explain what happened. I do eBIAB with a continuously recirculating mash, a pourover sparge after pulling the bag and a recirculating boil in the original kettle. All hops are pitched commando both in the boil and in the 170F whirlpool. No filters anywhere in the process other than the bag. My Chugger pump is plenty powerful and I've never had a problem with hops clogging my valve or my plate chiller.
Still, I transfer an awful lot of hop matter to the fermenter, so I decided to put an empty brewing bag in the kettle before the boil and before pitching any hops. I got a lot of strange noises, hissing and otherwise, and when I investigated the bag was billowing strangely and some of the wort was migrating up the side of the bag and out of the kettle, so I decided to complete the boil without the recirculating lid. After sixty minutes I chilled to 170F, pitched about 1.5oz of cryo-hops, and put the lid back on for a whirlpool with my PID set to hold the temp at 170F.
More hissing and other strange noises from the kettle, but nevertheless I persisted. After 20 minutes, I decided it was time to remove the bag, chill, and transfer to the fermenter. This is where things got weird. When I lifted the bag, almost all the wort came with it! OK, I thought, I will wait and let it drain slowly through the very fine mesh, but virtually nothing happened. The brew pretty much stayed in the bag! I wound up sticking a knife through the bag to let it drain. A fair portion of the hop matter drained back into the brew-kettle with it, but so it goes.
How does this make any sense at all? I investigated the empty bag further after transferring the wort to the fermenter. Cleaning the bag made no difference. Water would not flow through the bag anywhere other than the knife hole. Even weirder, when I turned the bag inside-out, with the seams on the outside, water flowed through the bag just fine. A one way bag?
I have two of these bags and I have used the other one to mash grain for many brews with no issues. What made the second bag go rogue like this?
A couple of asides with the benefit of thinking this over a bit. I am guessing that the strange nolses originated from the pump cavitating. The Chugger is a pretty tough beast and I don't seem to have caused any permanent harm to the pump. The hissing was probably wort hitting the heating element. I think the element is OK because it is not discolored following the ordeal, but I am not really sure about that.
Has anyone else had an experience like this? How can a bag flow in only one direction?
Still, I transfer an awful lot of hop matter to the fermenter, so I decided to put an empty brewing bag in the kettle before the boil and before pitching any hops. I got a lot of strange noises, hissing and otherwise, and when I investigated the bag was billowing strangely and some of the wort was migrating up the side of the bag and out of the kettle, so I decided to complete the boil without the recirculating lid. After sixty minutes I chilled to 170F, pitched about 1.5oz of cryo-hops, and put the lid back on for a whirlpool with my PID set to hold the temp at 170F.
More hissing and other strange noises from the kettle, but nevertheless I persisted. After 20 minutes, I decided it was time to remove the bag, chill, and transfer to the fermenter. This is where things got weird. When I lifted the bag, almost all the wort came with it! OK, I thought, I will wait and let it drain slowly through the very fine mesh, but virtually nothing happened. The brew pretty much stayed in the bag! I wound up sticking a knife through the bag to let it drain. A fair portion of the hop matter drained back into the brew-kettle with it, but so it goes.
How does this make any sense at all? I investigated the empty bag further after transferring the wort to the fermenter. Cleaning the bag made no difference. Water would not flow through the bag anywhere other than the knife hole. Even weirder, when I turned the bag inside-out, with the seams on the outside, water flowed through the bag just fine. A one way bag?
I have two of these bags and I have used the other one to mash grain for many brews with no issues. What made the second bag go rogue like this?
A couple of asides with the benefit of thinking this over a bit. I am guessing that the strange nolses originated from the pump cavitating. The Chugger is a pretty tough beast and I don't seem to have caused any permanent harm to the pump. The hissing was probably wort hitting the heating element. I think the element is OK because it is not discolored following the ordeal, but I am not really sure about that.
Has anyone else had an experience like this? How can a bag flow in only one direction?