Homebrew Beer Blog

I was looking through the site here and noticed I've left out a letter in my HERMS setup, the Recirculation. I recently posted about my pump setup and purge valve, so I'll cover two types of recirculation in my system: mash and chilling.

Mashing

The mashing recirculation is fairly simple. There are numerous ways of making a HREMS as I described in the theory post. My system recirculates continuously, so there's nothing really special going on with the pump controls. I just turn it on, and eyeball the flow rate to about 1/3 speed or so. The pump runs during the entire mash. For more details on the HERMS, check out the HERMS page.

One other item of interest here may be the wort return to the mash-tun. You'll want to have some system that will return the wort as evenly as possible so not to promote channeling and unnecessary aeration. I use a pretty simple setup where I have a length of silicone tubing coiled on top of the mash. It creates a gentile whirlpool above the mash, which I think helps with channeling.

Chilling

The chilling recirculation is based off of Jamil's whirlpool setup, but I've taken it up a notch with the double chiller. Jamil's site has a lot of details that's not worth rehashing here, but basically what I do is I dunk the chiller in the kettle during the last 15 minutes, then start recirculating boiling wort. When I kill the flame and start the chill, it knocks down the temps very quickly. I can get down to 10+ my chill water temp in about 10-15 minutes and to my chill water temp in about 20 to 25. When the tap water is running down to in the 50's this goes real quick.

For those concerned with DMS, the SMM precursor should be halted below 140, and this setup knocks the entire kettle down below 140 in like a minute. Also, hop alpha acid isomerization will end the faster you get the entire wort off of the boil, plus that should help retain more of the volatile hop aromas. Compare these two items to a plate or counter-flow setup where much of the wort stands at near boiling for the duration of the chill. The importance of this is debatable at this scale, but it's still kind of cool.

I used to own a Therminator and hands down this system is a considerable net time savings, not to mention piece of mind about cleaning and sanitising. To sanitize, I just stick in the boil and to clean I just dunk it in a bucket of cleaner (made from waste chill water, which later gets dumped into the boil kettle for cleaning) and hose it off to dry.

To build the chilling setup, I found a coil of 1/2 ID copper tubing at the scrap yard. I cut off a 2-3 foot length and gave it a slight S-shaped bend Then I soldered an 90-degree arm, then a at the end a 45-degree elbow fitting. This gives me my directed jet. I just did it this way to avoid messing up the copper with my bending, plus I was already soldering the pipe fitting on the other end. If you can get a bending tool, that may worth the small investment.

The whirlpool action isn't anything dramatic. It's just enough to get some movement in the kettle, which is really all you need to really improve chilling. I don't think the pump is sufficient to actually whirlpool trub, so usually after I'm done chilling, I'll pull it out, then give it a gentile spin with a big sanitized stainless spoon, then let it settle out as I clean up. If I'm using whole hops with my false bottom, I don't even bother whirlpooling the trub since the wort is pretty well filtered by the hops do to the recirculation.

Flow Rates

Flow rates can be important. In the mash, you shouldn't need to recirculate a whole lot of volume, and like I said, I usually go w/ my pump open only about 1/3. The mash can gum up the works, however, and prime spots are cheap barbs/nipples and quick disconnects. For chilling, it's perhaps an even bigger deal with each restriction lowering the flow. Less flow, poorer the whirlpool and longer the chilling.

To really improve my pump flow in both of these tasks was to swap out all my hose barbs with full bore connectors, and then replaced my disconnects with tri-clover fittings. Anything that obstructs or restricts the flow makes a significant difference, not only in the flow rates, but in clogging the works up. Take note of the differences in hose barbs. You will likely find similar differences between ball valves, so keep an eye on the bore size. More than once, I had various disconnects and cheap connectors choke up the works with pellet hops and clumps of grain.