Recirculation manifold.

Another important element to modify in my mash tun setup was the manifold I would use to recirculate the mash tun liquor from the bottom to the top of the grain bed without disturbing it. Recirculation was necessary to get an even temperature throughout the grain bed when heating and to get the grain particles and dust recirculated through the grain bed so they don’t end up in my boil kettle.

Design

Once again, it seemed that the best material for this would be 1x1" stainless tubing. I had already built a recirculation manifold and was fairly pleased with it. There were some exceptions and needed adjustments though and here are a few of them:

The old manifold went across the mash tun only partially and didn’t distribute the grains and water evenly,

The manifold used to sit on the grain bed and sink into it while pumping,

Its was hard to clean the manifold afterwards because the grains got stuck in it

The old manifold couldn’t be remove without removing the sparge ring.

To fix these problems, I figured on using the same U shaped design as the previous incarnation but this time longer and a little more narrower so it could fit in-between the gap of the sparge manifold. In this manner, I could pull either manifold to the top of the lid to get it out of the way without hitting one another. In my old manifold, the grains would get trapped inside of the legs and had to be flushed with a lot of water to get them out. In the new design, I place caps on the ends that could be removed when cleaning rather than welding them to the ends.. In addition, I also cut the hole from the neck to the manifold square this time so the grains wouldn’t collect in the stem. I would keep the manifold from sinking by clamping it to the mash lid (see mash lid below).

Figure 2: Recirculation manifold with end caps for cleaning.