So I recently picked up a pump to transfer strike water and spare water from an HLT to my mashtun, which is a standard orange 10g Home Depot cooler.
Would it be effective to pump water into the ball valve into the mash tun (bottom up) or would it be better to run the hose into the top of the cooler and pump in water from the top? Or, does it matter?
I’m trying to set something up where I don’t have to remove the mash tun lid very much to maintain a more consistent temp inside.
Thanks!
I don’t think it matters much, but pumping it through the ball valve means that you could underlet your water into the grain bed. If low oxygen brewing mattered to you, then that approach could matter.
I really like pumping into the valve. When you underlet/pump bottom up, there are no dough balls. Plus the added benefit of no O2 is a plus.
The one possible downside I’ve found with underletting is that it doesn’t seem to diste ibute the heat as evenly as adding water from the top. That means I have to stir more, which might negate any possible low oxygen effects. More investigation is required for me.
The upside of underletting slowly I’ve come to appreciate is the uniform wetting of the grain bed which I’ve found to result in no dough balls. I stir very little and gently just to check. I really like the results of the technique.
I can imagine this would be an issue for cooler brewers. When direct firing and constantly recirculating, this really isn’t an issue.
I do realize, however, that cooler brewers make up a big contingent of homebrewers. You have to know your equipment and how it responds to certain techniques.
Truthfully, I didn’t decide to underlet for any low oxygen benefits. It just works for my new brewing process. If I get any benefits, it would be great, but it’s not a big consideration for me.
I don’t underlet, but I effect a similar wetting from below by very slowly lowering my grain basket into the strike water (pre-boiled and chilled to strike temp before adding salts and sulfites) over the course of a few minutes, letting all entrained air slowly get pushed out of the grain from the bottom, with little to no bubbles occurring. I use a ceiling mounted pulley hoist to lower the grain basket into the kettle containing the strike water (full volume no sparge).
After a gentle stir to assure no clumps, I then recirc on a closed loop HERMS arrangement.
It seems to work well enough on my system; YSMV, of course.
Honestly, a lot of people just like to underlet for reasons already pointed out and not for anything related to LOB. Which is cool, because everything doesn’t always have to boil down to the oxygen discussion. Some techniques are just cool on their own.
For me, it was more about practical then low oxy or cool. Once I decided I was going to use the Mash and Boil and a HLT, it became the easiest way to get the liquor from there to the tun.
Does one have to underlet slowly? If so, how slow? My HLT is raised above the MT, so I gravity drain. Would that be slow enough? It would be nice to have fewer dough balls, and better LDO.
I don’t think it matters. I go as fast as my pump will pump it.
For me it is just a matter of trying to reduce potential oxidation in the mashing process. I agree that if LODO is not the objective, fill it fast and stir it like crazy to equalize the temperature and eliminate the doughballs. For LODO, you want to underlet slowly enough to prevent air pockets that bubble to the surface.
That’s interesting! So underletting reduces or eliminates dough balls without stirring. Hmmmm! I’ll have to try that next brew (which is an Irish Red Ale happening on 11/18). I suspect that the HLT will fill more slowly, but all I have to do to set it up is run the hose to the ball valve, so no big deal.
Charlie
I underlet as fast as the pump goes. It may take some stirring, and recirculation, but I hit my target temp
I’ve found that underlet pumping from the HLT to the MLT (Coleman cooler) slowly does eliminate dough balls in my system.
How slow is a good question. I have a linear flow valve to control pump volume accurately that I open to 1/4” measured from the machined seam on the housing to the edge of the adjustment cap. I have no idea what that gap setting translates to in volume over time. However, it seems to wet the grain in a very controlled uniform way. I gently stir to check but since doing it this way I’ve yet to find a dough ball.
I use the same gap setting every time I mash in. I also use the same setting to recirculate during the mash and to transfer to the BK after the mash.
Once mashed in, I am at a slightly lower temp than mash in temp. I allow the RIMS to bring me up the ~5 degrees to the mash in temp as I begin the mash recirculation.
Although I could underlet from my HLT to my mash tun, I just gravity fill my mash tun with the required amount of liquor (my HLT is higher than my mash tun), heat it to strike temp and stir in the grain. Now I admit I am not a LODO brewer, but it makes things easier for me and I always hit my mash temp target.
If I ever decide to build a new brew system, something that has been bouncing around in my head like a BB in a boxcar, I might consider a setup that would allow me to underlet with a pump.
If you are doing as a piece part of a system whose goal is to help exclude oxygen, then slower is likely better so as to to not suck air in the HLT vessel, through connections, etc. Slower means better mixing without having to stir, which is also important for that specific goal.
If that’s not the goal, then speed shouldn’t matter, especially if you are just going to stir it up real good anyway.
I’m finally back to brewing regularly after a long hiatus. I made a lot of changes to my rig. I’m a cooler MT user. I found that pumping into my grain makes it easier. No doughballs at all. I went back to using my HERMS, and continual recirculation. Loving the results with underletting, just easier for my process.
I used to underlet until I went the herms route. I can’t see an easy way to recirculate and get that dope grain bed that makes my wort Oh-So-Clear.