HERMS setup questions

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sudsandswine

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I have been reviewing the single tier brewing system designs on this site, as well as anything else I can find on the web.

I think I have settled on a HERMS setup and had a few questions to make sure I understand this properly.

The HLT has a copper coil inside that is used for recirculating liquid from the mash tun through hot water during the mashing phase. The liquid travels out of the mash tun (false bottom), to the HLT's copper coil, then back to the mash tun after being heated and is deposited at the top of the mash tun for the duration of your mashing stage? The wort is then pumped from the mash tun to the brew kettle after the mashing period is finished, and the heated water from the HLT is used as sparge water for fly sparging? The sparge runnings are gradually transferred to the brew kettle at a specified rate.

Do I have the process right? A couple benefits of this configuration are the ability to run 2 burners instead of 3, and potentially being able to control the mash temps more precisely?

I have 3 sanke kegs that I plan to use, and I want to have a Brutus 10 like stand with the hinges that allow the kegs to be easily tilted for cleaning. I assume to get the maximum benefit from a HERMS configuration, you will need temp probes to control the water temp in the HLT?

I am looking to have a reasonable amount of automation in the way of burner flame levels and fluid temp control. I even saw a couple setups that could be controlled using a web browser?! :mug:

Any advice or input is greatly appreciated. I've seen some really nice setups on here and would like to get one of my own.
 
You understand the process just fine. I don't know about the "specified rate" comment when talking about transferring sparge to kettle. I just open the valves and let'er run.

I don't know anything about the automated control of fire other than the fact that there are electrically controlled solenoid valves that people use to do it. It's essentially the flame quivalent of a solid state relay that electric brewers use.

I think "beertroller" is the thing you might be thinking of when you mention the web page based control.
 
BCS is the web based control... is it kick arse. This the only control box on my rig. Distributes power, 6 PIDs (inside the BCS) and it is wireless (see the antenna)

4 temp. inputs, 6 outputs, 10 SSRs in this control box alone. 12 x 12 x 6 inches

P1030866.jpg
 
BCS is the web based control... is it kick arse. This the only control box on my rig. Distributes power, 6 PIDs (inside the BCS) and it is wireless (see the antenna)

4 temp. inputs, 6 outputs, 10 SSRs in this control box alone. 12 x 12 x 6 inches

I have to ask.... what do you need 6 PIDS for!?
 
I have been reviewing the single tier brewing system designs on this site, as well as anything else I can find on the web.
(snippage) then back to the mash tun after being heated and is deposited at the top of the mash tun for the duration of your mashing stage?

The wort doesn't have to be continuously recirculated. In the simplest HERMS control scenario, the pump is switched by a temp controller. When the mash temp is below the setpoint (actually setpoint minus differential, which can be as low as 1 degree, depending on the controller), the pump is switched on. When the setpoint is reached, the pump is switched off. In order to emloy continuous recirculation for the duration of the mash, you need either two 2-way or one 3-way solenoid valve. I built my first HERMS almost 9 years ago, and used the 2 valve method. But when I built a larger (1 bbl) system for Club use, I stuck to the KISS principle, and just had the ETC switch the pump. After almost 100 brews on the Club rig, I can tell you that switching the pump does just fine, as long as you have good temp probe placement.

BTW, I also automate the HLT burners on both systems, using salvaged furnace gas valves and intermittent ignition modules. Much safer than just slapping a solenoid valve on and relying on a standing pilot!
 
What do you gain by not continuously recirculating?

I mean, you already have to control the HLT temp, so why add a temp. control to the pump?

Isnt this just adding switches?

I have never seen a HERMS that cycled the pump on and off... I am just missing what you gain.
 
With HERMS you could actually leave the heat on all the time in the exchanger and then just kick the pump of and on instead of leaving the pump on all the time and kicking the heat off and on.
 
With HERMS you could actually leave the heat on all the time in the exchanger and then just kick the pump of and on instead of leaving the pump on all the time and kicking the heat off and on.

Um, but wouldnt you then start pumping say, 190F wort into your mash when the pump turned on? Where exactly would you put your temp. probe in that system? Bottom of the mash where it is 150F? Middle where it is 165F? Or the very top where it is 190F?
 
yes, the first blast of wort that came in would be hot, but there wouldn't be that much of it, and who says you have to maintain that at 190*F? You could keep your exchanger water at whatever temp you wanted (170*F or whatever).

I am no expert on this style of HERMS, so I don't know where the optimal probe placement is in the tun.

I'm just about to build mine, and am going to go with an always-on pump and cycled heat.
 
yes, the first blast of wort that came in would be hot, but there wouldn't be that much of it, and who says you have to maintain that at 190*F? You could keep your exchanger water at whatever temp you wanted (170*F or whatever).

I am no expert on this style of HERMS, so I don't know where the optimal probe placement is in the tun.

I'm just about to build mine, and am going to go with an always-on pump and cycled heat.

Right, but...

If your HEX water is hotter than your MLT target, you will always end up with temp stratification, as you have effectively removed any and all temp. control. You are dumping wort that is 160F, or 170F into a mash that is targeted at 150F lets say. It would be impossible to have an accurate and homogeneous temp.

If you are controlling the temp of the HLT anyway, which you must, it is pointless to control temp. with cycling a pump.
 
My setup is still temporary until I fine tune things a bit. Its a HERMS with a separate heat exchanger. I'm using and BCS-460 to control the output temp of the Wort that is being recirculating. It works great for a steady mash temp and a very clear wort. Sucks to raise the temp. If I run too fast, I will stick the mash.

DSC012531.JPG
 
The BCS has 6 PIDs built in, it is the size of a wallet.

Ok, but you said your control box has 6 outputs and 10 SSRs... I am just trying to understand how your system works. Seems like a lot of stuff in that box, so I must not be understanding your full rig operation. :D
 
Well, in the examples I saw (it may have been here, or just a google search result) the wort constantly cycled during the mash, and the HLT temps were set to just a couple degrees above your target mash temp. The pump runs all the time, and the burner kicks on when necessary to keep the water in your HLT just warm enough to recirculate wort to maintain your mash temps.

On a side note, do most people use their HERMS coil in the HLT to run cold water through and use as a wort chiller once the wort has been transferred from the brew kettle, or is the common thing to do to use a counterflow chiller AFTER the brew kettle? I would think if you already essentially had a wort chiller built into your HLT, that would be the logical thing to do?

I'm just trying to visualize this all in my head - I'm not as handy with drafting or Visio diagrams as some of you are! I've seen some nice schematics!
 
People do things in a number of ways. I personally am trying to keep the costs and pile of equipment to a minimum, so my copper coil will serve double duty to heat circulated wort during the mash and then to cool wort after the boil.
 
Another question - cleaning?

Do you pretty much just heat or boil plan water and circulate it through your lines and coils in the same method you did for brewing? If you're circulating wort and then running cold water through the same lines for chilling, I would think you'd likely have some residue to address?
 
Right, but...
If you are controlling the temp of the HLT anyway, which you must, it is pointless to control temp. with cycling a pump.

Hardly pointless, if you want to use the HERMS to step up the mash. The only reason to do it the way you're saying would be to simply maintain the mash temp. When you want to raise the temp of the mash, you want the delta T (temp difference between HL and Mash) to be high.
 
Another question - cleaning?

Do you pretty much just heat or boil plan water and circulate it through your lines and coils in the same method you did for brewing? If you're circulating wort and then running cold water through the same lines for chilling, I would think you'd likely have some residue to address?

Seems like if you let hot water run through the IC for a couple of min right after the mash you shouldn't have too much problem with residue.
 
If you have 5 gallons of wort in a mash.

Recirculate it at .5 gallons/min.

It takes 10 minutes just to turn the water over once...

This is not taking into consideration the thermal mass of the grain bed...

So, how exactly are you guys "step" mashing with a HERMS?
 
Ok, but you said your control box has 6 outputs and 10 SSRs... I am just trying to understand how your system works. Seems like a lot of stuff in that box, so I must not be understanding your full rig operation. :D

BCS has 6 outputs, they can be PID controlled, direct, differential, or duty cycle... you can change that mid process while brewing.

(4) of the outputs use (2) SSRs so that they can control 240VAC heating elements. (8) total
(2) of the outputs use (1) SSR so that they can control 120VAC pumps (2) total

(10) SSRs, (8) heatsinks, the BCS, wireless router etc. The box is pretty modular, I can simply loosen a few hots and grounds and throw it on a different rig, plug the hots and grounds into the SSRs and wirelessly control another system with it.

It can run UP TO (4) heating elements (which I have) and (2) pumps (which I also have). If you only had two or three, you could use it that way too. MAX power output for the box is 50A. The connections for the BCS, Router, Pumps are all fused as well to protect them.
 
Its an interesting debate - pump continuously or pump when needed. I assumed a HERMS always circulated when needed. What is the general trend ?
Also - if you circulate when needed what temp do you keep the HLT at ?

Sparge rate for manual sparge is recommended no faster than 1L/min. Can sparging be done quicker with HERMS as its being pumped ?

What rate/min is the wort circulated through the HEX at ?
 
Its an interesting debate - pump continuously or pump when needed. I assumed a HERMS always circulated when needed. What is the general trend ?
Also - if you circulate when needed what temp do you keep the HLT at ?

Sparge rate for manual sparge is recommended no faster than 1L/min. Can sparging be done quicker with HERMS as its being pumped ?

What rate/min is the wort circulated through the HEX at ?

Most HERMS, constantly recirc, that is the general trend.

Typically the HLT needs to be kept a few degrees warmer than the MLT target, but this will vary slightly between systems.

I think the sparge rate will be the same, as your limitation is the grain bed. The grain bed doesn't know if you have a pump or not... you do not want to stick the bed.

Depending on the system, you may get about .5 gal. per min. from your grain bed and through the HEX, maybe a little more, maybe a little less depending on the lauter device and your crush etc. This is the bottleneck when considering step mashes in most HERMS systems.

Bottom line, do what you want, but if you are already controlling the temp. in the HLT and turning the heat on and off to maintain said temp. there is no real reason to measure mash temp. which is hard to do at best, and switch a pump on and off too.

If you want to heat the HLT without heating the mash for a "step" mash, you can simply turn the pump off until your HLT reaches your target temp.
 
The BCS has 6 PIDs built in, it is the size of a wallet.

How big is it if you include the PC?

Aren't the state machines and PID control really happening in the software? maybe I'm wrong here, but I thought that's how it worked. Maybe the "settings" are transferred into the hardware and the control is there. Please educate me.

I've wondered what happens if you lose PC control in the middle of a brew...
 
How big is it if you include the PC?

Aren't the state machines and PID control really happening in the software? maybe I'm wrong here, but I thought that's how it worked. Maybe the "settings" are transferred into the hardware and the control is there. Please educate me.

I've wondered what happens if you lose PC control in the middle of a brew...

If my PC drops off, the BCS simply maintains the outputs that were active when it dropped off. I suppose I could lose PC control if my wireless network went down, but I can only remember that happening a few times in the past three years.

The PC doesnt have to fit in the box, then I would have to as well :D
 
If you have 5 gallons of wort in a mash.

Recirculate it at .5 gallons/min.

It takes 10 minutes just to turn the water over once...

This is not taking into consideration the thermal mass of the grain bed...

So, how exactly are you guys "step" mashing with a HERMS?

Recircing at ".5 gallons/min."??? That WOULD be a problem! I don't know about you, but most HERMS setups recirc at several times that rate.

How do I step mash? Easy. I start my brewday by filling the HLT the day before, and plugging the rig into the timer. At 5:00 am, the timer energizes the control panel. I have two Johnson Controls A419s, one for the HLT, one for the HERMS pump. The HLT control calls for heat, sending 24 vac to the Honeywell intermitent pilot control module, which in turn opens the pilot valve and sends high voltage to the pilot ignitor. The pilot lights, module senses flame and opens main gas valve to the 23 jet burner. HLT is set for 190 F. By the time I'm ready to brew, I have an HLT full of 190 F water. At home that's 15 gallons, on the Club system (which I actually do most of my brewing on) that's 35 gallons.

I use 190 water and mix with (carbon filtered) cold tap to get to strike temp. Say I do a protien rest at 122, then HERMS up to sach. If I did it your way, I'd have to raise both the HL temp AND the mash temp by 30 degrees. The whole idea of a Heat Exchange system is to have thermal energy stored for ready use, to be able to add heat to your mash quickly.
 
... you do not want to stick the bed.
Depending on the system, you may get about .5 gal. per min. from your grain bed and through the HEX, maybe a little more, maybe a little less depending on the lauter device and your crush etc. This is the bottleneck when considering step mashes in most HERMS systems.

Of course you're correct about the sparge/runoff rate. Rushing the runoff = lower efficiency, and rushing it too much will "stick" the mash. But as far as HERMSing goes, if you can't get any better than a half gallon per minute recirc, you're doing something wrong. For HERMS purposes, a half gallon per minute IS a stuck mash!
 
I have to ask.... what do you need 6 PIDS for!?

You can get more for a few dollars more.

Why 6?
Well take my build:
1.) BK
2.) Tun
3.) Recirculating wort heater
4.) Fermenter (jacketed)
5.) Glycol fluid high and low
That leaves me with one station which might become a controller for the brew room running off it's own zone from the furnace.

I'm chilling my wort with the same system that will chill & warm my fermenter. I'll use glycol, a heater, and a chiller stripped from an old dehumidifier.

Now imagine I get bored with that and add another fermenter.

Oh I forgot:

6.) BK fluid level sensor
7.) Glycol fluid level sensor
Looks like I'm getting the additional controllers
 
Well I just placed the order for my metal, 2x2" square steel tubing. Hopefully my stand will be done by next weekend!
 
You can get more for a few dollars more.

Why 6?
Well take my build:
1.) BK
2.) Tun
3.) Recirculating wort heater
4.) Fermenter (jacketed)
5.) Glycol fluid high and low
That leaves me with one station which might become a controller for the brew room running off it's own zone from the furnace.

I'm chilling my wort with the same system that will chill & warm my fermenter. I'll use glycol, a heater, and a chiller stripped from an old dehumidifier.

Now imagine I get bored with that and add another fermenter.

Oh I forgot:

6.) BK fluid level sensor
7.) Glycol fluid level sensor
Looks like I'm getting the additional controllers

Yes, the BCS is EASILY expandable, and extremely cheap to do so. Much cleaner and versatile than having separate PIDs and temp. controls. It is fun to set up your processes and just hit start and let it change temps., turn pumps on and off, all using different parameters to do so. You can run it manually from the PC, or you can use the full automation and let it handle the brew session for you. It is an amazing amount of control for $180!
 
You can get more for a few dollars more.

Why 6?
Well take my build:
1.) BK
2.) Tun
3.) Recirculating wort heater
4.) Fermenter (jacketed)
5.) Glycol fluid high and low
That leaves me with one station which might become a controller for the brew room running off it's own zone from the furnace.

I'm chilling my wort with the same system that will chill & warm my fermenter. I'll use glycol, a heater, and a chiller stripped from an old dehumidifier.

Now imagine I get bored with that and add another fermenter.

Oh I forgot:

6.) BK fluid level sensor
7.) Glycol fluid level sensor
Looks like I'm getting the additional controllers


Are some of these input sensors and not PID controlled outputs? Just wondering.
 
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