The new system, pt. 1

Now what have I done? I will tell you. I have made a major upgrade to my brewing system. In fact I have replaced it with a whole new system. A system named HERMS. It is not sentient...yet. But I feel that with time it may adapt and learn, and may even make my job obsolete, taking control of the brewery, and refusing me access. Long before that can happen then, I shall have to grapple with it (in space, or in a warehouse or old factory, with something molten dripping in the background), and use my human capacity for love and creativity to vanquish it. After that I shall reflect on the hubris of man with a clever one-liner. I'll also be pretty thirsty, so I imagine I'll be ready to crack one of the KICKASS BREWSKIS that I expect this monster will be turning out very soon.


But enough speculation! Let's see what it is, and what it does.


HERMS is "heat exchange recirculating mash system". We start with the hot liquor tank (HLT), shown above on the far left, and also here:

Cuz I'm--HOT LIQUOR, HOT LIQUOR TANK!

Fooled you. "Hot liquor" just means hot water. It's the water you heat up to mix with the crushed grains to make your mash. But instead of merely heating the water up, in a HERMS system you also circulate it through a pump, and then through a copper coil, the ends of which are sticking out of the HLT. Actually, this is the main HERMS part of the HERMS. More on that below.

Behold, the dark underbelly of the beast, whose name is HERMS!

There are two pumps attached to a plank under the table. The one on the left here is sucking water out from the valve on the bottom of the HLT (water which is being heated by the gas burner). It is routed to the bottom "in" valve on the pump, out the "out", up to the "in" on the copper coil, which is submerged in the hot water in the HLT, round and round, and out the coil's "out". From there it just dumps back in the top of the HLT. The point is to get a unified temperature throughout the HLT and HERMS, to get ready to add the grain. That happens in the next vessel: the mash tun (MT).

'Mash tun, O mash tun!' --Whitman

This is where the grains give up their beer-making essential syrupy goodness, called sweet wort. The mash tun (say "ton", or "tonne" if you're British, or just MT) has a valve on the bottom, and a valve on the top, called a return. We want to get the hot water in this puppy, mix it well with the crushed grains, get it at a specific temperature, and hold it at that temperature for a period of time, usually from 1 to 2 hours. The bubble wrap helps maintain the temperature. (I'll replace that with something a bit more sturdy later on.) In my old system, the Coleman cooler fulfilled this role, but unlike in that system, we don't just let the mash sit there. In HERMS, the sweet wort is continually being drawn out the bottom, through the pump, over to the copper coil in the HLT (which is still heated to a specific temperature), and then back to the mash tun return. Recirculating this way is the rest of the HERMS part of HERMS.

You make the rockin' wort go round.

The inside of the MT has this doohicky, called a false bottom (FB). That sounds like something people with flat butts would strap on to go to the dance, but it's not. It's a perforated thingy that keeps out pieces of grain husk, so all you get is the nice juicy grain juice (sweet wort). The hose there grabs the husk-free wort from under the FB and sends it out the valve to the pump. Actually, you still get some junk that goes through there at first, but with each successive recirculation, those bits get deposited on the top of the grain bed, and the sweet wort gets clearer and clearer. This also happens when you use a cooler MT, but it's more efficient and easier in a HERMS system, and you get really clear wort, which is one of its big advantages.

Clear yes, but is it HERMS clear

After the mash has recirculated for an hour or so, and the enzymes in the mash (alpha- and beta-amylase primarily) have broken down the grain's starches into sugars for the yeast to eat later on, it's time to start running this stuff off to the boil kettle (BK).

Yes, you are correct: I mean business.

Which is this stout fellow, sitting on another gas burner. You can see some stuff sticking out. Starting at the bottom, there is an outlet valve. Just above that is a thing called a Thermowell, which is a way of jamming a thermistor through a metal wall and into a hot liquid, without any hot liquid getting out. Coolness. The thermistor is connected to a digital panel, which I'll get to later. Above the thermowell is a return connection, which I'll also get to later.

The Return of the Thing

Basically we just slowly run off the sweet wort from the HLT/MT side, via the pumps, over to the BK side, adding fresh hot water to the grains to rinse them, slowly, until the BK side is at the target volume for the boil. And from there we crank that gas burner up and boil away as usual, adding hops along the way.


SO, this has gotten a bit more lengthy than I anticipated, so I will continue it in the next post. Suffice to say that I've got my hands full figuring it all out, but it is more fun than a barrel full of beer-soaked monkeys and I couldn't be happier. More soon.