My son asked me to help him put together a HERMS system, including the controller. After looking at several online, we liked Michael's unit here on the Skrilnetz E-HERMS section the best. I went about acquiring all of the parts using the list and sources Michael had used. I highly recommend Auberins.com (Auber Instruments). Their quality of their parts is excellent and they were very helpful on the phone during the ordering stage.
We only made a few changes to the system. The biggest one was that I felt the summer Georgia heat outside was not going to be adequate cooling for the heat sinks so we chose to install them inside the box along with a cooling fan and exhaust air vent. I chose a slightly larger case, one that was 12 x 14 x 8, only because I found it cheaper than the 12 x 12 x 6 that Michael used. A side benefit of this was that the additional real estate inside the box does make it easier to lay out and wire. I incorporated a second hot bus but in the end, that was really unneeded. I added a separate fuse for the fan so that it could be easily turned off if needed. I added an additional 120v accessory receptacle, too. I changed the location of the meter current pickup coil so that both the main 120v red line output from the main contactor and a line from the Hot Red Bus passes through it. Now it will show all current, not just heater element current. I wired the alarm so that an alarm from either the HLT PID or the Mash PID will turn on the alarm. That allows my son to have an alarm for too high or too low temp conditions in both the HLT and the Mash at the same time. And because the unit is not wall mounted, I installed rubber feet and u-bar handles. The controller box is done except for a plastic exhaust air hole grill, which is still on order. If I had it to over again, I would have made the exhaust air hole round instead of square because it would have been easier to find a cover for it. We used labels similar to Michael's project from the same source, George Bouwmeester at signsbannerstags.ca - they look excellent and are very inexpensive. One note on the meter: The placard on the back was not logical to those of us in the western world. So, I wound up initially installing it upside down. I should have looked at Michael's photo better on that one!
Attached is a collection of photos of the construction, which was a lot of fun. Michael's circuit schematics were excellent and I am very comfortable at both electric and electronic work so building it was no problem at all. It was really fun to build. My advice for anyone attempting it is to go slow, be methodic, and keep a good record of what you are doing during the wiring stage. At completion of each phase, check the circuits with a meter and the power up that section before going on. Much easier to identify problems at that point instead of when everything is done. Also I would add that it is MUCH easier to keep track of wiring progress and troubleshoot later (if needed) when you spend a few extra bucks and buy multiple colors of the wire in the gauges needed. You will note that my wiring layout makes it easy to identify what is going where and if it is HOT or not. NO green unless it is ground!!! Wire is really expensive by the foot but Home Depot had all of the 10 & 14awg wire in the colors I wanted. Ebay was a source for inexpensive multi-color 22awg wire bundles. I think it is worth the extra $20 bucks or so to have color-coded wiring.
I can't say enough how great a job Michael did on his design and on the web pages / photos / schematics / parts list, etc that made my build possible. And, he was great at getting back to me with answers to questions. Many thanks, Michael!
I would be happy to answer any questions about my build. I will try to add a couple of final photos of the interior wire bundles soon.
David B
Thank you so much David for taking the time to explain your build and to post images!
The control panel looks great! The wiring is so clean and well done.
I totally agree with you to go slow when wiring the panel. Testing after each step will avoid long troubleshooting at the end. I also agree that using right color coding is very important. I neglected that in my build as I had a lot of wires on hand, just not the right colors (I used color tape to identify wires).
Good luck with the new system. Would be great to hear back from you once your HERMS is ready. I’m always curious to see different approaches.
All the best!
Hello, Michael. It's been awhile so here is an update. The controller is totally done and testing fine. We installed heater elements in the HLT and Boiler tanks last week and tested heating. The heat sinks inside the controller box cooled just fine with the fan circulating air over the coils. We did a test run to rapid boil in the boiler with approx. 11 gals of very cold tap water and it was boiling in 53 minutes with the 5500w heating element. Meter on the controller showed 240-v & 5335 watts. That's a lot more water than son, Michael, will ever use in the beer making process, but we thought we would fill it to see.
We installed the o-ring and washer BETWEEN the tank and the electrical box to get a good seal. We did not have luck with the o-ring on the inside behind the nut. We tried to use one on each side but the fitting was not long enough to get the nut threaded on. Also, we ground down or beveled the six end points of the nut on the side that touches the tank. The curvature of the tank made the nut's 6 outer points interfere with the tank and not tighten adequately. Just ground it down with grinder... a few seconds at each of the six points.
Our last challenge has been the coil in the HLT. Not much real estate in there to get the compression couples to tighten adequately. Still trying to solve that. All holes are drilled. We just need to find a way to get in there to get to the fittings with two wrenches.
I would highly recommend people use the correct size high quality hole-saw bits made to cut steel. Believe me, in the end, having good bits will be well worth the money. We used one for all of the 3/4 in holes. It goes through the stainless steel like butter. We did not have one for the 1.25 in hole and used a step bit. Or really two. Or really two plus a high speed dremel tool carbide cutter to get it all the way after the two bits gave out.
Probably will be a couple more months before Michael and I can get together to finish things up. Will keep you posted. Hope the book sale is going well!
Many thanks for the update David!
The controller looks great!
I had the same issue getting the HERMS coils leak free with the compression fittings. It took me a while to get that tight. Pretty hard to get the wrench into the right place.
I was able to drill into my kettles using a cheap step drill, but I see you are using sanke kegs and the stainless is much thicker than my pots.
Keep up the good work!
@David, I love the idea of adding a simple 110v fan on the panel and mounting the heat sinks inside the box. It's hard to tell from the pictures but it looks like you added a fan speed controller? Can you tell me a little more about that?
I think you are mistaking the fuse with a speed control. As far as I can see, he has no speed control on the fan.
RyanJ, Michael is correct. We do not have any speed control on the fan. It runs any time main power is switched on. I installed a separate fuse just for the fan so that we would have a way to protect it separately from the other fused components AND be able to deactivate it if needed. The fan is working great, pulling in a significant volume of air which circulates and exits at the top of the case on the same side as the fan. Air is flowing directly over both of the heat sinks. Makes for a cleaner looking unit with everything inside.
