Dedicated Herms Guide, Problems And Solution Thread

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Sorry I meant that figure of 1 degree per minute that gets thrown around. I always thought it was to stop denaturing of enzymes or something but then HERMS designs run a large differential so in the time the mash liquor gets through the hex coil it could potentially jump 4 or 5 degrees in one pass.

And the more detail the better mate, I am probably being a pain in the ass with the questions but I've dumped alot of coin into the build and am a little nervous about how it will all run. I'm feeling a bit more confident now though, I'd say 50ft of coil will give me a good heat transfer, heating with 8kw should be no issue and a flow rate of 6L/min should all result in ramping to mash out in half an hour or so. I generally don't do step mashes so its really only from 65-67 ramping to 76.
 
Consider a standard single batch, with a hermit on something like Camo6's system his recirc would be around 7-8LPM with liquor to grits ratio of 3.5-4L/kg. You've got 20L of liquid. If the hex is powered sufficiently the exit temp should be at target from the get go. So a 7 deg step @ 1Deg/min would have the liquor turned over the tun 2 and a half times. I dare say on those numbers you'd be more like 1.2 - 1.5 Deg/min.

Now double batch that with the same 7 Deg step and your better than 1Deg/min goes out the window but not significantly, step done in around 10mins.

ED: I did think of another way to increase flow: Run two coils in parallel
 
Moad said:
Sorry I meant that figure of 1 degree per minute that gets thrown around. I always thought it was to stop denaturing of enzymes or something but then HERMS designs run a large differential so in the time the mash liquor gets through the hex coil it could potentially jump 4 or 5 degrees in one pass.
Ah - I get ya now (eventually). I'd mash in at 65 if I could, but it's resulted in dough balls a few times, never had it mashing in with 50 - 55 deg water. So I'm not really interested in the temps between 55 and 65, just want it up there ASAP. For any steps after that, the HLT will ramp at ~1 deg/min with the coil out matching the HLT, and the mash tun outlet following about 10mins after (or whatever the full mash volume recirc time + a bit equals).

Moad said:
And the more detail the better mate, I am probably being a pain in the ass with the questions but I've dumped alot of coin into the build and am a little nervous about how it will all run.
PS - we don't talk about the war. They might be looking... :ph34r:
 
Awesome, so theoretically on my system:

180L can be heated 10 degrees in approximately 15 minutes and I can also turn the entire mash over in 15 minutes so the max time to get the mash up the 10 degrees would be 30 minutes but more likely less than that. I'm fine if that is the case in reality.

Still though I can't find much info on the 1 degree/min ramp rate, more than that apparently denatures enzymes. So does that mean you are denaturing when you are turning your mash from 55-65 in a pass through the coil?
 
Interesting question, my feel would be no, at mash in your taking those same enzimes from 20c to 55, or in my case 65, MHB would be the man to ask though.
 
Moad said:
Awesome, so theoretically on my system:

180L can be heated 10 degrees in approximately 15 minutes and I can also turn the entire mash over in 15 minutes so the max time to get the mash up the 10 degrees would be 30 minutes but more likely less than that. I'm fine if that is the case in reality.

Still though I can't find much info on the 1 degree/min ramp rate, more than that apparently denatures enzymes. So does that mean you are denaturing when you are turning your mash from 55-65 in a pass through the coil?
A prolonged step at 50 - 55 is used for a protein rest. When using normal (fully modified) malts I *dont* want to stay there for a prolonged time, so denature away...
 
Yeah valid point about 20 to 55/65. Obviously it works for Herms brewers so perhaps a non issue. Research required...

I'll report back once the electrical stuff is done and I can run some tests
 
Well after a lot of discussion, enlightenment, research, and realisation some of which took place here. The flow rate issue has if not been resolve then the root cause found.
So to start Chugger, March and I believe KK pumps are all designed to be dual frequency 50hz/60hz 240v pumps able to operate both here and the US. Unfortunately the rotational speed of the pump is directly affected by the frequency. At zero head; the 20% more power our northern cousins have makes only a minor difference, however as head increases so does the gap between the 50hz and 60hz curves.
Chugger only show one curve for their pump; the 60hz. Luckily March show both, note the max flow rate( even at 50hz) for this pump at zero is higher than the Chugger but has the same head @ 50hz. On the march 50hz have a look where the 6LM mark it's fairly close to 4m (13ft) head; now check the chugger graph for flow rate at 13ft Which is 3.5gmp or 13LMP. That 10hz difference is costing Aussie brewers everywhere half the designed flow rate.

Changing or converting frequencies is discussed in my first link so I won't delve any deeper.

But I didn't give up and I did find a solution or two.

A few years back Qldkev did some running around and we had a bulk buy run on the MP 15RM @50hz 16LPM 2.4m (I believe this is the rebranded KK grey pump)

Kev also Grabbed a more powerful pump, though it had 3/4 thread so not many takers that was the MP 20RM@50hz 27LPM 3.1m


I went for a look about and found bigger again though with 1" thread MP 55RM@50hz 60LPM 5.6m

Further search had me looking at a 24v DC pump with a SS head that looks like it had been rip off the chugger. The best bit 24DC is 24DC anywhere the other thing is the graph is lineal Topsflo TD5-A24-2705-P/AU 24v @ 1.4A 35w 27LPM 5m


*flow rates quoted are max flow at zero head
* Meters quoted are max head
# Note to Keg King or vendors there of: if what I have stated here is incorrect please direct me to the Manufacturers web site with the correct detail.

I'm sure if a BB were started for either of the linked items those prices would change some what, eg the topsflo can be had for US$87 a piece (min order 500)

ED:TYpung
 
Hey guys, I'm helping build a new 200l 3V rig.

I've previously used a Hermit coil with great results on an old 80l 3V.
https://onlinebrewingsupplies.com/herm-itr-heat-exchange/herm-itr-2-4kw-hx-heat-exchange-full-kit

For 200L will a Hermit coil full kit be big enough?
Or should I go 25' or 50' s/s coil in the HLT like everyone in the states do?

Only doing a single step mash with a mash out and batch sparge. If need be I can use coil and HLT to keep a constant temp and batch sparge with mash out temp.

Cheers
 
I'm running 50ft stainless in HLT for 120L rig and testing indicates 1.5 degrees per minute ramping.

Without reading back through the whole thread,what differential are people seeing between hex outlet and mash run probe. I'm seeing 2 degree difference, the my never catches up. I expected .5-1 degree difference not 2.

Should I be bumping temp at hex up by the 2 degrees or should I only let it get to my desired mash temp regardless of losses in the bed.

I don't want to insulate the MT and hide all that sexy stainless
 
This thread has so much good information, i highly recommend reading as much as you can. However here is some of the nuggets i have extracted from it.

WHY USE SEPARATE HEX
Separate HEX is possible more common in Aus due to our stadard plugs and wiring. UK has 240V16A, US has 120V 20A commonly paired to 240V 20A etc etc. We have a pissy 2400W as standard. A couple of people who questioned why use a HEX have admited to having 4-5000W or more available.

To decide on a HEX vs HLT coil you need to work backward.
1. What is your total energy available
2. What size mash do you want
3. What ramp speed do you want
Remember, The HEX/HLT output will get to set point long before the mash does. Our ramp time is taken from when the HEX output starts to move until temp exiting MLT hits set point.

To achevice 1degC/min* for various volumes of HEX + Mash assuming 85% efficency
2400W - 30L,
3600W - 44L
4800W - 59L
5500W - 67L, etc

For example, a 2400W with a 5L Hex could theroetically heat 25L in a MLT @ 1degC/min
Thermal mass of the grain obviously effects this.
That same 2400W would heat 25L in the HLT and 25L in the mash around 0.6degC/min

Small HEX equals less total volume to heat for a given Mash.
If you have sufficient Wattage to heat the HLT and MLT at the same time, do it and skip the HEX.


COMMON HEX/HLT SETUP
Once youve chosen your method size (3L Pot or full HLT are common),
put enough copper/SS to transfer the energy being produced.

Small Hex
3-4m is enough to remove 2.4-3.6kW from a 2-4L pot.
This works as the HEX temp will be much hotter than set point.
The element will be controlled by the wort temp exiting the HEX.
This setup is stable (low overshoot) when the coil volume and HEX pot volume are as close as possible
ie Cram as much copper in the pot as you can.

Coil in HLT ( Much more detail elsewhere)
15m+ in a HLT should see the output match the HLT temp.
This length is required as the HLT will only be the same or slightly higher than the required set point

Counter Flow Exchanger CFX
A third way is a Counter flow exchanger, often used as a chiller (CFC)
Cycle the Mash through the inner coil and HLT hot water through the outer
Like the HEX, the temp in the HLT can be hotter than set point without scalding wort, the wort temp exiting can be controlled by amount of Hot water flow through the CFX.

All of these work better when as much as possible is insulated, any lost heat is a loss in efficency.

MY SETUP

I can use both a HEX and CFX and both work for 1 deg/min temp rises using a single 2400W element for a 20-25L mash.
The current experiment is to quickly brew ~40L by leveraging both
Basically the idea is to have the 2400W element on all the time, storing heat in the HLT while the MLT is at set point.

Process
During a rest,
1. wort is pumped through a 3m coil in a 3L HEX. The HEX element cycles on a little to maintain the output temp.
2. The HLT is set to 95 deg. The ouput electronics logic lets only one SSR come on at a time,
any moment the HEX is not on, heat is applied to the HLT

When its time to step,
1. MLT pump is routed half through the hex and half through the CFX internal coil.
2. The HEX set point is raised and the element comes on full, stopping the HLT element.
3. The HLT water is pumped through the CFX outer coil, heating the wort.
4. When the HLT temp drops to same as the MLT temp, isolate the CFX and the HEX finishes off the work.

Early testing of the procedure is very tasty, i mean promising
 
Looking at adding a herms to my BIAB setup for a couple of reasons.

First, its a major PITA to step mash on gas, easy to overshoot your target temp for the next step if your not watching like a hawk

Second, I want to go electric as gas usage with my nasa is ridiculous. I have limited power available though. Calcs ive looked at, suggest I would need at least 4800W to be able to ramp at an acceptable rate. Both circuits I have won't support this and not possible to get one installed as I am renting. After a lot of reading, it would seem herms could possibly let me get away with potentially halving this requirement.

Total noob at all this though,so have a few questions.

My typical mash vol is around 80L, full volume double batch BIAB. What size HLT would I be looking at to fire this setup?

What Length coil would I be looking at?

Is it possible to use a temperature controller to control it all, or do I need to look at going to a PID?

What size element would be appropriate?

I will probably go for the silver kk mag drive pump they look like they would do the job.

Things I already have at my disposal I could repurpose for this to keep cost down:

14L exposed element urn
30L aluminium stock pot
50L Keggle that's already got a ball valve welded in (Previous single batch rig)
2x 1m lengths of silicone hose.

Would like to ramp as quick as possible

cheers for the help, head is spinning trying to work out where to start.
 
It would seem ive overlooked firing the kettle for the boil not really going to be that helpful/beneficial after all is it
 
MB-squared

Ill be getting a bcs soon and could you elaborate a bit more on how you set up your HLT and Mash temp?
How does your HLT temp not overshoot your mash temp etc?
I've never used that calculator but here's my real-world experience. I fill up my HLT with ~40L of cold water (I've been told to never use hot tap water!) and my MT with 30L of cold water. I turn on both the water and wort pumps as well as the 5.5kw element in the HLT. Actually, I start the "get mash-in temp" function on my BCS. I then turn around, weigh out my grain, mill my grain and measure out my salt and acid additions. Right about the time I finish up those chores, the BCS starts dinging, letting me know that my MT is up to temp.** I'd say it takes somewhere between 30 and 40 minutes.

**Moad, note that I set up the BCS to cycle the element on/off based on the temp probe at the HLT-out valve, but the "get mash temp" process doesn't exit until the temp probe in the MT has reached my desired 'mash in' temp. Again, that's ~15 minutes after the HLT has reached my desired temp.
 
Hi gavin8019, I think it will be easier to understand once you get your BCS. With the BCS, each stage of your brew day is broken down into a "process" (e.g. "get mash-in temp", "protein rest", "saccharification" etc.). A process terminates after a specified time or temp has been reached. On my system, I have a temp probe on my HLT and one on my Mash Tun; I have an electric element in my HLT. The "get mash-in temp" process heats the HLT until the HLT temp probe reaches the specified temp but that process does not terminate until the Mash Tun temp probe reaches the specified temp. So no overheating -- must maintains the mash-in temp in the HLT until the Mash Tun is ready. Does that make sense?
 
Well after a lot of discussion, enlightenment, research, and realisation some of which took place here. The flow rate issue has if not been resolve then the root cause found.
So to start Chugger, March and I believe KK pumps are all designed to be dual frequency 50hz/60hz 240v pumps able to operate both here and the US. Unfortunately the rotational speed of the pump is directly affected by the frequency. At zero head; the 20% more power our northern cousins have makes only a minor difference, however as head increases so does the gap between the 50hz and 60hz curves.
Chugger only show one curve for their pump; the 60hz. Luckily March show both, note the max flow rate( even at 50hz) for this pump at zero is higher than the Chugger but has the same head @ 50hz. On the march 50hz have a look where the 6LM mark it's fairly close to 4m (13ft) head; now check the chugger graph for flow rate at 13ft Which is 3.5gmp or 13LMP. That 10hz difference is costing Aussie brewers everywhere half the designed flow rate.

Changing or converting frequencies is discussed in my first link so I won't delve any deeper.

But I didn't give up and I did find a solution or two.

A few years back Qldkev did some running around and we had a bulk buy run on the MP 15RM @50hz 16LPM 2.4m (I believe this is the rebranded KK grey pump)

Kev also Grabbed a more powerful pump, though it had 3/4 thread so not many takers that was the MP 20RM@50hz 27LPM 3.1m


I went for a look about and found bigger again though with 1" thread MP 55RM@50hz 60LPM 5.6m

Further search had me looking at a 24v DC pump with a SS head that looks like it had been rip off the chugger. The best bit 24DC is 24DC anywhere the other thing is the graph is lineal Topsflo TD5-A24-2705-P/AU 24v @ 1.4A 35w 27LPM 5m


*flow rates quoted are max flow at zero head
* Meters quoted are max head
# Note to Keg King or vendors there of: if what I have stated here is incorrect please direct me to the Manufacturers web site with the correct detail.

I'm sure if a BB were started for either of the linked items those prices would change some what, eg the topsflo can be had for US$87 a piece (min order 500)

ED:TYpung


Hey MJ, just did some research myself and found the same pump, in fact it's now sold by an aussie ebay supplier at similar price bracket to the Chugger and quoted as superior to the Chugger/March pumps because it is DC supply and therefore truly variable speed (although given the magnetic drive part I am unsure the merits of that statement.

http://www.ebay.com.au/itm/Stainles...377180?hash=item25d9b60edc:g:9~8AAOSwMvtZUH1h

So.... has anyone actually tried one of these and can vouch for the performance etc?

s-l1600.jpg
 
Hey MJ, just did some research myself and found the same pump, in fact it's now sold by an aussie ebay supplier at similar price bracket to the Chugger and quoted as superior to the Chugger/March pumps because it is DC supply and therefore truly variable speed (although given the magnetic drive part I am unsure the merits of that statement.

http://www.ebay.com.au/itm/Stainles...377180?hash=item25d9b60edc:g:9~8AAOSwMvtZUH1h

So.... has anyone actually tried one of these and can vouch for the performance etc?

s-l1600.jpg
I'm sure your aware of pump curves LPM vs Head, and indeed when graphed those figures for an AC pump create a curve. DC pumps are lineal, so a straight line from zero head high volume to max head and no volume.
 
Really? I have not seen a linear pump curve myself before, because the function that governs flow and pressure drop (head) is not a linear equation, so how is it different for DC simply due to the power supply aspect?
 
Some solid Engrish in that eBay advert for a bushless pump.
I'm not sure of your explanation there MJ, the only difference between the DC and AC pump is the drive. It's still a centrifugal pump so will behave the same way, not a straight line as you imply. Adjusting the input speed however will allow control over the power (because, simply put, the faster the impeller spins the more pressure / flow) which is not as simple asn an AC drive in the domestic scale. Note however the quoted pump has a simple AC converter for power so you'd still need to buy some sort of PWM controller to adjust the speed.
 
Anyone using their herms hex as an instant hot water heater for sparging?
I'm setting up a large 1V system (quad batch minimum) with a small volume hex, and am toying with the idea of running tap water directly through the hex to sparge. I have never bothered sparging in the past with double batches and have always had good efficiency, however I've been told I will need to for bigger batches.
 

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