Brewery Build – Introduction, HERMS Coil, Drilling Boilermakers

It’s probably time I start posting about my brewery.

I’m building an all electric Heat Exchanger Recirculating Mash System (HERMS) brewery that will live in my garage. The brewery is intended to fix all the problems I had when I was brewing in Kansas and make brewing enjoyable instead of a horrible chore.

The basic gist of the system will be 3 20 gallons pots, the Hot Liquor Tun (HLT), the Mash Lauter Tun (MLT) and the Boil Kettle (BK). The HLT will contain a large coil of stainless steel tubing that wort will circulate through to change the temperature of the liquid in the MLT. This is the HERMS. The system will use two pumps to move all the liquids around and several (10, perhaps?) solenoid valves to make on the fly plumbing changes. The goal is that the system will require no manual plumbing changes and (ideally) could run almost 100% automatically.

I’ve been designing, drawing, dreaming and buying stuff for a month or so now. I made a giant shopping list and have been trying to buy the stuff needed to get a single kettle up and running and then go from there. This weekend I finally had most of that stuff together so I got to work. I wanted to build the HLT first since that would be the most complex. The first step was to fabricate the HERMS coil as the size of that would determine the positioning of many things. I picked up 50′ of 1/2″ OD stainless tubing McMaster and when it arrived it was in a 24″ diameter coil. Unfortunately I needed a 12″ coil. So, after doing some reading and asking questions I filled the whole thing with nice, dry sand (which was a pain in the ass) and very slowly and painfully coiled it around an old 12″ diameter pot I had laying around. This worked pretty well but it was HARD work! My coil turned out to be 12″ in diameter and about 8″ high when compressed.

Side note: When the project is done I will post a spreadsheet with prices and sources of all the parts. I don’t feel like putting them all in these posts as I go along.

That was Saturday. Sunday I measured everything, draw some dots and set out to drill some holes in my Boilermaker. This was fairly difficult but I think it was my own fear of drilling in the expensive pots more than anything. I drilled a 1/8″ pilot hole using lots of cutting oil and plenty of pressure with my hand drill and then widened each hole to 13/16 with a large Unibit. Lots of pressure, cutting oil and some good hearing and eye protection and it wasn’t really that bad. I drilled two holes on the left side of the pot. One at 5″ from the bottom and one at 13″ from the bottom. These are the entry and exit holes for the HERMS coil. I would have liked the coil to sit a little lower but I needed room for the heating element which will be at 3″ from the bottom. The holes needed to be slightly larger than 13/16″ so I cleaned them up just a little bit with a sanding wheel in my Dremel.

The next step was mounting the coil. I had intended to use a pair of weldless bulkheads, two 90 degree elbows and just run the coil right into the elbows. This turned out to not really work. Because of the angles involved the coil would rest against the side of the kettle. I tried using a coupler to move the whole assembly further into the pot but that made it go too far to one side and hit again. When I had really wanted to do from the beginning was have the coil terminate in two straight pieces from a 90 degree bend so it could go straight into compression fittings through the kettle wall. Unfortunately I had had some trouble doing 90 degree bends in the stainless tubing. Since this ended up being necessary I got to work on that.

To get my 90 degree bends in the tubing I first straightened about 16″ of tubing at the top of the coil. I did this by slipping a plumbing spring over the coil then straightening it about an inch at a time in my vice. This worked really nicely. Once it was straight I put it back in the vice around where I wanted my 90″ bend and started pulling on it. I would bend a few degrees and then move it in the vice a quarter inch or so and then repeat. This was hard work but it got the job done. The only problem is that the resulting bend has a very slight kink to it. I don’t think it will cause too much restriction but only time will tell. I tried to reshape the kink in the vise a little and had moderate success.

That’s where I finished on Sunday. I have another 90 degree bend to make and then I should be able to mount the coil. I am thinking I might pick up a tube bender from Harbor Freight and try that. They sell one for $30 that looks like it might be capable.

So, tonight I’ll try to make the other bend, mount the coil and test it all out for water tightness. After that it’s on to installing the first heating element. I bought a 1.25″ chassis punch that should make that a lot easier but it’s not here yet. Should be here soon. I’ll also be receiving a bunch of control panel parts tomorrow that I can start laying out and seeing what works.

Also, I should mention I built and am selling a custom display for the BrewTroller brewery controller I am using. Check it out!

And finally this is a quick rundown of the specs and major components of the brewery I am building:

  • All electric HERMs brewing system. 240v, 50A input.
  • 3 20 gallon Boilermaker kettles.
  • 240v 4500 watt HLT and 5500 watt BK.
  • Control provided by a BrewTroller v3.3 w/ 16 relay output board and BrewTroller software 1.2.
  • 3 Custom PID temperature displays.
  • 2 March 809-HS pumps for fluid movement.
  • 7-10 stainless steel 12v solenoid valves for fluid routing.
  • Plate style stainless steel wort chiller with 20 plates.
  • Silicone tubing plumbing to start, stainless hard plumbing eventually.
  • Custom stainless brewing stand. I’ll be welding this once my TIG skills are a little better.
  • Custom control panel with On/Auto/Off controls for pumps, heaters and all valves. Also includes 3 of my BrewTroller PID Displays, the BrewTroller LCD and rotary encoder for input.
  • All stainless pipe fittings.
  • Inline oxygen injection during pump to fermenters.
  • Constant recirculation of MLT and HLT to avoid temperature stratification.

I think that’s it for now!

One thought on “Brewery Build – Introduction, HERMS Coil, Drilling Boilermakers”

  1. Really excited about this, you are building exactly what I am planning to build, are you planning to use the plumbing design schematic from the brewtroller site? If incorporating your PID displays is pretty easy I will be using them as well.

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