HERMS Design Advice

[Mike_McBrew]

Hello all,

I am hoping to take advantage of your experience in designing a HERMS. I am in the middle of pricing the system and wanted to know if there are any glaring errors. I realise that every one will have their own preferences and I hope to ask some more specific questions later but in the first instance it's a question about major errors and omissions.

In order of events the idea would be to :
1. Heat the strike water in the boil kettle
2. Heat the water in the HLT to the temperature for recirculating the wort
3. Pump the strike water into the Mash tun
4. Add the grist
5. Start recirculating the wort through the HLT
6a. If the HLT water is at sparge temp. at the end of the mash then use that to supply the sparge water, pushing it through the coil so as to simplify the piping
6b. If the HLT water is not at the sparge temperature then heat the sparge water in the boil kettle and supply the mash tun directly
7. Pump the wort into the boil kettle
8. Add hops and boil
9. Cool the boiled liquid via a cooling coil (not shown)
10. Pump into the fermenter

The HLT is sized smaller so as to minimise the duration of temperature changes in multi step mashes.
The boil kettle is sized larger so as to avoid splashing / foaming over.
I have a false bottom on top of the mash tun as ell as the bottom to spread the recirculating wort across the entire surface. I have also seen people use the recirculation to cause (deliberately) rotation but I haven't understood the advantages and disadvantages yet - I'll ask this question in a separate thread in a different forum.
I would intend to use two pumps although if the piping is too long to recirculate (to maintain a consistent temperature) the water in the HLT (without too much cooling during its travels) then I'd add a third pump in order to shorten to circuit.
I'd intend that all entry / exit to the vessels would be tapped. The valves would be three way, one exit and two entries with a tap to switch between the entries.

Thanks in advance for all and any help.

Mike

 

[Mike_McBrew]

I'm guessing I haven't asked a good question.
Any help as to what was wrong with the question?

 

[iijakii]

Well, you really just haven't asked any questions lol. Your process seems standard and fine.

 

[Rockn_M]

That's pretty much what I do. I don't use a false bottom on the top of the mash tun and I only use 2 pumps. One water to recurculate the HLT and then one to pump through the heat exchange in the HLT and the same pump, pumps the sweet wort to the boil kettle then finally through the chiller and into the fermentor.

I built a Kal clone from http://www.theelectricbrewery.com/. He pretty much gives you step by step instructions on how to build and use his setup.

Good Luck!

 

[LandoLincoln]

It's hard to find the question or questions. Normally one uses a question mark for that kind of thing.

Rotation of the recirculating wort isn't a thing, as far as I know. It may rotate up top but I don't think people are doing it in order to gain some kind of advantage over non-rotational recirculation.

6b should be 6a and vice versa.

6a (which was 6b) would be "if the sparge liquor temp is not at the proper sparging temp at the end of the mash, the HLT heating element will be used to bring it to the appropriate temp before sparging has begun."

6b would take place while 7 is going on.

False bottoms can be very pricey. I would recommend finding a cheaper alternative for a top sparge arm.

Adding a third pump is completely unnecessary.

I have no idea why you'd need three-way valves.

 

[Mike_McBrew]

Thanks all. That gives me confidence that I haven't completely misunderstood something. I can now price it up and see if it passes the wife test without worrying that my pricing is way out.

I was hoping to do it for a lot less than the the estimated $5700 - $6700 for the electric brewery, not buying Blichmann, not building the panel, buying £125 pumps and not $350 etc. Still, at $20 for the plans I might buy them anyway.

Thanks again,
Mike

 

[DurtyChemist]

I'm looking into a complete HERMS build myself using Sanke kegs. I don't think you'll need more than 2 pumps and you could do it with 1 if you consider batch sparging.

heat strike water in HLT or MT if you can. Heating MT directly just elimiates one step to transfer water (liquor)
Add grains in MT and mash.
Tube from the bottom of the MT into and out of the pump to the HERMS coil. I haven't seen anyone say which way (top to bottom/bottom to top) is correct or why you'd do one over another.
The force of going through the HERMS coil will pump out of the coil into a sparge arm. gravity will work.
Heat water surround HERMS coil to 168 for mash out.
stop pumping into the HERMS coil and start pumping from MT to BK.
Once the MT is empty you batch sparge with your HLT water into the mash, through the HERMS coil and either through the MT again or into the BK. HERMS coil rinsed, mashout complete, grains rinsed and everything ends up in the boil kettle.

A second pump would give you the ability to fly sparge with the HERMS coil. Depending on your efficiency you might save enough to pay yourself back for buying a second pump plus connections and tubing.

 

[Ozarks Mountain Brewery]

Have you visited The electric brewery, his system is sound and has been used by hundreds of people around the world

http://www.theelectricbrewery.com/

 

[TrickyDick]

Don't forget to recirculate the mash before running through the HERMS coil. Seems would be a good idea.

 

[Mike_McBrew]

@trickydicky I'm not sure what you mean there? Recirculation happens through the HERMS coil, are you suggesting a bypass? What would the advantage be?

 

[cantrell00]

@trickydicky I'm not sure what you mean there? Recirculation happens through the HERMS coil, are you suggesting a bypass? What would the advantage be?

Speculating here but is sounds like the OP are implying to recirculate the MLT to set the grain bed prior to routing mash fluid through the coil.

Maybe I am wrong but that is the only reasoning I can think of.

Unnecessary in my experience.. I gradually open up my pump and set the grain bed while recirculating through the HERMS..

Where do you intend to place the probes for the HLT/MLT/HERMS?

I found the best place was on the MLT return from the HERMS. This represented the tightest delta between the HLT & MASH temp. Typically a 2-3 degree variance.

I also have a probe on my kettle for monitoring temps while cooling, hopstands, etc.

Dial probes on HLT and MLT. MLT is a 6" that extends all the way into the mash.

 

[Gameface]

Despite what others have said, I think a third pump is a very good addition to a HERMS system. Not necessary at all, especially if not doing back to back batches, but if you do want to do back to back I consider it to be essential to get the full potential of that type of system.

The HLT needs to be recirculating anytime you're using it with the HERMS coil, or anytime you want the temp of the HLT water to be uniform. I personally don't want that pump to ever have wort in it. It's a water pump.

Obviously you want to be recirculating your mash any time you're mashing. You'll also need that pump during sparging.

If you're going to use an immersion chiller, or doing hop stands/whirlpool, or want to sanitize a counter flow chiller or plate chiller, or pump to your fermenter you'll need a pump available for that.

If you're doing a back to back brew session with two pumps something will be sitting and waiting for a pump and that can add well over an hour to a back to back brew day.

 

[Gameface]

Also, just wait for your HLT to come up to temp for your sparge water. Don't use the BK for your sparge water because, obviously, you need a place for your wort to go while your sparge. That place is the boil kettle, which it sounds like might be full of sparge water.

I don't think a smaller HLT is a great idea. You can mount your coil lower so that you don't have to fill it as full, but you want enough space to keep all your sparge water. Yes, it takes longer to get to temps the more water you have to heat, but a 5500W element can heat a good deal of water within a reasonable amount of time.

You would be well served stopping by www.theelectricbrewery.com

Kal's design has become the standard HERMS design. He explains everything very well. The system is open source and flexible, so if you want to do something differently it's easy to start with his design and modify from there. No need to reinvent the wheel.

 

[TrickyDick]

To make sure you don't inadvertently plug up your coil with grain husks if any get past the filter/screen, as might often occur during the initial mashing in and recirculation. Probably more of a precaution than a necessity.

TD

 

[Gameface]

If I had three pumps (and I plan on adding a third soon) I would use one that was fed from the HLT and either recirc'd through the HLT or went to the HERMS coil. TTHe second would be fed from the MT and would either recirc through the HERMS or fill the BK. The third would be fed from the BK and would either recirc/whirlpool the BK, recirc through a counterflow chiller back to BK (for sanitation), or pump to fermentation vessel (via counterflow chiller).

Each vessel would have it's own pump.

I have a plumbing design that doesn't involve disconnecting any hoses. I worry about stagnant sweet wort interacting with chilled wort as I pump to my fermenter. The third pump would allow me to completely segregate water from sweet wort from chilled wort.

I did my first back to back brew day a few weeks ago and I had to stop recirculating my mash while I whirlpooled my BK and then transferred to my fermentor. Then I went back and started my mash out. I could have started my mash out considerably sooner had I had a third pump. If someone knows how to do all that with two pumps I'd be all ears.

 

[TrickyDick]

Speculating here but is sounds like the OP are implying to recirculate the MLT to set the grain bed prior to routing mash fluid through the coil.

Maybe I am wrong but that is the only reasoning I can think of.

Unnecessary in my experience.. I gradually open up my pump and set the grain bed while recirculating through the HERMS..

Hmm. I've not used a HERMS before. I am designing my system around a three vessel HLT/HERMS electric setup. I had once built a sparge/ recirculation arm from 1/2' PVC and the SOB plugged with grain husks on its first use. I was un-fixable but a major disappointment and not a large investment so it got thrown in the trash. That was early in my all-grain brewing and I later discovered that the false bottom in my cooler mash tun was being tilted off the bottom allowing husks to enter the runoff. Air bubble had developed below the liner and insulation of the cooler and when heated it expanded. Mash screen instead of false bottom solved that problem. Anyways, I thought it would be possible that small amounts of grains could enter the coil and might cause problems. Glad to know that happens not to be an issue.


TD

 

[Gameface]

Hmm. I've not used a HERMS before. I am designing my system around a three vessel HLT/HERMS electric setup. I had once built a sparge/ recirculation arm from 1/2' PVC and the SOB plugged with grain husks on its first use. I was un-fixable but a major disappointment and not a large investment so it got thrown in the trash. That was early in my all-grain brewing and I later discovered that the false bottom in my cooler mash tun was being tilted off the bottom allowing husks to enter the runoff. Air bubble had developed below the liner and insulation of the cooler and when heated it expanded. Mash screen instead of false bottom solved that problem. Anyways, I thought it would be possible that small amounts of grains could enter the coil and might cause problems. Glad to know that happens not to be an issue.


TD

The HERMS coil has a large enough diameter that I don't think clogging would be an issue unless you were basically trying to pump mash grist through it with no filter or false bottom at all. Even then it might not clog although I wouldn't want to risk it.

 

[Mike_McBrew]

Soft start to avoid stuck mash / Coil bypass to avoid clogging recirculation system

Think I might add a couple more 3 way valves and a bypass tube for the recirculation system, it can't hurt and compared to the total cost it's almost invisible.

I think a third pump is a very good addition to a HERMS system

In my system it would not be a fully fledged pump, just a small 24V pump to recirculate the HLT water to stop temperature gradients forming around the coil.

Each vessel would have it's own pump.

Nice idea, bit expensive in the first build but will keep it in mind for future upgrades.

Where do you intend to place the probes for the HLT/MLT/HERMS?

Temp probe for the HLT would go on the recirculation exit point (into the mash tun) with an STC 1000 on the HLT as an over-temperature safety precaution (a heater with no temperature measurement on the vessel itself sounds like a bad plan).
I'd have standard dial gauges on all vessels, one each on HLT and BK, two on the mash tun, one near the top, one near the bottom to see what temperature gradient the mash has.

Also, just wait for your HLT to come up to temp for your sparge water. Don't use the BK for your sparge water because, obviously, you need a place for your wort to go while your sparge. That place is the boil kettle, which it sounds like might be full of sparge water

Very good point, that's exactly why I posted this, to see what little things I'd overlooked.

www.theelectricbrewery.com

Very much aware of it, will probably buy the plans as a reference point but want to try and reduce the cost from $6000 - $7500 USD. My system here is 2500 euros (without a bench to put it on).

Thanks all,
Mike

 

[Gameface]

You can build a system around Kal's design for much much less than $6000 USD. You can further modify it and make it for well under $1000 USD.

But the basic process flow and setup are solid. If you're gonna deviate from that I'd suggest you have a well thought out reason for why and how.

 

[bbohanon]

The HERMS coil has a large enough diameter that I don't think clogging would be an issue unless you were basically trying to pump mash grist through it with no filter or false bottom at all. Even then it might not clog although I wouldn't want to risk it.

I recirc right through my HERMS after dough-in. Its a 50ft, 1/2 inch SS HERMS Coil and never had it stick or plug firing up the recirc right after douging-in.
I have had it slow down due to the amount of wheat I was using, but thats occuring at the MT, not in the HERMS coil. I also use a dome false bottom and have not had an issue with it to date. Cheap, easy and zero deadspace.
For the record, I am getting 90-93% efficiency on my system but I also fly sparge for 60 mins and mill my grain just a tad finer than most do which helps efficiency as well.

The beauty of a HERMS system (outside of the great efficiency and it delivering clearer wort pre-boil due to the recircing, slow sparge which sets the grain bed better than any other system I have used) is that the sparge water will clean out the HERMS coil during the sparge so its maintenance free on the HLT.

I love my HERMS system and would not trade it for anything other system. The only thing I hated was the plate chiller I bought..I have since switched back over to an IM chiller again. The long term plan is to put another 50ft 1/2 coil in my BK as a perma-mount QDisconnect for my IM solution..Just cleaner and more sanitary than a plate chiller IMHO.

 

[TrickyDick]

#bbohanon
Thanks for the advice!
I hear you on the chiller. I have had all kinds over the years, and find that my home built 50' immersion gets more duty than the Therminator or even the Chillzilla.
I believe that I am going to be installing TC fitting adapters to the soldered MPT fittings on my Chillzilla (AKA Copper Counterflow Convoluted chiller). This seems to be a better solution than QD's and probably only leaves just a few threads exposed. Not a fan of the soldered drilled TC caps onto the tubing - seems as if it would be a weak and difficult solder joint. Not sure if I can get enough flow through the chiller to recirculate AND whirlpool or not. I think this is going to be my long term solution. Here in FL I can usually only chill to 80-82º without using ice water. However, I can chill down the rest of the way in my fermentors.

TD