I’ve been using a stainless braid ala Denny for years. This is a rectangular cooler with a spigot in the middle of the long side. It has worked really well when sparging via gravity, but when I added a pump, the braid couldn’t keep up with the flow rate (6" piece of braid).
I was thinking maybe i just need more surface area, so I put in a longer piece of braid (18") looped around in the cooler with a copper tee. This helped the flow rate, but it doesn’t always drain fully via the pump. Usually, by the time the pump loses prime, there are 3-4 qts of wort on both ends of the cooler where the braid loop doesn’t reach, and it takes forever to drain via gravity.
Has anybody solved this issue? Some sort of manifold / braid combo to keep the braid on the bottom? it doesn’t seem to be a stuck sparge issue, just not draining completely without the pump sucking air.
I batch sparge with the same basic setup, sans the pump. I often end up with liquid sitting on top for the mash while the main runnings come to a halt.
I’ve always assumed the gooey stuff that ends up on top of the mash is not allowing the liquid to move through freely. To get around it I use a large frosting knife to just cut through the top of the mash and let it run through, however slowly that happens.
It might be the same kind of thing and the pump is just making it happen sooner. Denny’s idea about using a grant would help a bit if that’s what’s happening.
Pump is not essential for sparging, as you have shown many of us
But I already use it for everything else that involves moving liquid (adding water from HLT, recirculating through the HERMS coil, whirlpool, filling fermenters). Maybe its just stubbornness that makes me want to use it for the sparge? Does nobody use a pump to sparge? What about flat brew sculptures?
The grant is an interesting idea, I didn’t even know what that was until I looked it up. I guess that’s one way to do it, with the downside of having another vessel to clean.
I guess this isn’t particularly helpful, but I use a pump to lauter through a CPVC manifold and at ~0.3 gpm I haven’t had any issues with completely draining the MLT (within reason; if I let it gravity drain over the next hour I’ll get up to another quart of wort out).
Thinking about the mechanics of the braid I’m not surprised it isn’t as effective; once it collapses at any point along its length the flow from the rest of braid is obstructed. I know I’ve seen people use something like coiled copper wire to keep the whole length of the braid stable.
Isn’t this simply a function of the run-off rate exceeding the draw at the end of the run? Slow the draw at the end (if you can time it well) and allow that last few quarts to drain by gravity, rather than the pump (i.e., close the valve on the cooler or “pinch the tubing shut for a moment”, disconnect the outflow tubing to the pump and put the outflow tubing into a collection bucket) and I bet it will work out fine.
I do have a coil of copper wire inside the braid to keep it from collapsing, so i don’t think that’s the problem. ynot called it, the runoff is exceeding the draw near the end. I’m not sure if this is because the braid is getting exposed to air, or because the grain bed is getting too compacted because of the fast flow rate.
Update: I brewed Friday and drained via gravity. Exact same result - about 3 qts left in the mash tun when the flow slowed to a trickle. The liquid was on both sides, again where the braid doesn’t reach. I did recirculate with the pump as normal, but disconnected for the runoff. This should not be an issue with batch sparging, not exactly sure why it’s happening.
Here’s an illustration of how the braid is arranged in the cooler, and where I get the undrained wort:
How fast are you pumping? You could be compacting your mash by pumping too fast.
How fine is your crush? You might be creating flour vs grits. I had to open my mill gap a bit when I added a pump. Grits allows flow through the bed.
How thick/thin is your mash? I had to thin my mash to allow a better lauter.
Does this happen with every mash? Some grain may not allow runoff as well as others. Wheat comes to mind.
Do you condition your grain before milling? Conditioned grain allows husks to remain intact creating a nice filter.
Once the MLT is drained, can you see any obstruction on the braid? I recently experienced untertieg. I had to stop, let the MLT ‘burp’, then start again.
Is the brain at the natural low point of the MLT? It seems like you have pools on the sides that may not be able to get to the braid.
If you drain the MLT and wait a few minutes, does the remaining wort then drain? I drain off the majority, wait a few minutes and get about another cup or so, wait a few minutes and get about another 1/4 cup.
I use a bazooka tube. In addition, I placed a stainless cooling rack to act as a false bottom and I use a fine mesh bag as a filter. The cooling rack give the wort about 1/4-1/2” below the grain bag allowing me to pump off the wort at ~.7 gpm. (The bazooka tube is a belt + suspenders approach and probably not required.)
BrewBama asks a key question, are you draining from the low point, or is the bottom surface of the cooler higher at the middle? Can’t fix gravity.
Also, your illustration (if it’s accurate and to scale) gave me an idea. I recall that Palmer, in How to Brew, has an appendix on lauter tun design and flow and such. He notes that the most even flow in a round cooler (stick with me) is achieved when the braid loop evenly divides the area of the bottom, half inside the braid and half outside. If you square that circle, your illustration of the area you’re successfully draining looks a lot like what he describes. So maybe you aren’t effectively drawing wort from the ends, because they lie outside the area of idealized flow. This could also mean you are oversparging the middle part of the grain bed and undersparging the ends, which could lead to both unrecovered extract and extracting some tannins and silicates from the oversparged part. If you are experiencing lower than expected efficiency or any other wort quality issues, it could point in this direction.
Maybe redesigning the braid to evenly divide the area of the tun could help.
Or maybe just using the BrewBama system of a “false bottom” by way of rack and grain bag is the simplest fix. Seems like he’s got this pretty much dialed in.
The OP is batch sparging m right? Palmer doesn’t address that. I don’t know exactly what’s going on here, but I can tell you that my straight line down the center braid doesn’t suffer from this problem. Could it be a case of trying too hard?
You are using an actual stainless steel braided line and not one that “looks” like stainless steel, right? There are some out there made of some sort of nylon that appears to be stainless but it’s not.
Batch sparge or fly, it seemed to me his issue could be uneven flow in certain regions of the cooler. His picture reminded me of what Palmer found, so I just thought I’d throw it out there.
I’m not sure, ultimately, that I’d be worried in a batch sparge. In a fly sparge you have to have even flow in order to extract the whole mass of grain. I thought the whole point of batch sparging was that stirring in the second batch of water took care of that, and all you have to do is drain all the liquid off. As long as the OP is able to do that eventually, even if it’s slow at the ends, no problem then.
