HERMS build

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charliebrown52

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OK so i have been planning this for a while and have a few questions that i have not been able to find the answers to

i currently do mostly 5 gal brews and use BIAB method in a keggle

so my plan is to go a different route than a traditional HERMS system, i have read a few people talk about my plan but not heard om anyone that has results

i plan to add a hlt with a coil heated by a source TBD at a constant near boiling temperature and then use pid to control my pump instead of constant re circulation

now i know that most people recirculate the entire mash and control there heat source so my question is does any one actually control there pump instead of the heat source and if so what are your results

i am not concerned with perfectly filtered crystal clear wort or step mashing i am simply looking for steady mash temps
 

augiedoggy

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How exactly would the pid control the pump to maintain a consistent temp? by constantly turning the pump on and off? Well to keep it simple that would ruin the pump fairly fast in most cases.
If you mean to keep the pump running and just vary the pump speed somehow by keeping the ssr operating at a very fast pwm rate with it that might work but then you are still vastly increasing the chance for a stuck sparge... all in all even it you got it to work it would be an inferior solution with more limitations than just going with a simple herms or rims setup which has the "other" benefits you dont care about for some reason... why reinvent the wheel and overcomplicate things while decreasing reliability.... Also how do you plan on sparging with this "near boiling" water in your HLT?

I'm curious if there is something I am missing or just do not understand that might give this solution some sort of advantage?

My $50 rims tube keeps my mash within 2 degrees the whole time and its simple.... herms is even simpler with less chance of disaster...
 

Beernik

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I had this thought too. I'm also slowly building up from a keggle BIAB to a HERMS.

I realized the problem is that would encourage thermal stratification of the mash. The wort sitting idle in the HLT would be boiling hot when the pump kicks on and the you have boiling hot wort in the top of your mash and too cold of wort in the bottom of the mash still.

The pump will keep running until the heat from the wort that just left pump works it's way down to your temp probe. By then, you've probably way overshot the desired average mash temperature because of all the boiling hot wort you just recirculated into the mash.

Even with constant stirring it seems like a guaranteed way to overshoot mash temperatures.
 

jeffmeh

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And the very hot water would certainly denature enzymes before it cooled to mash temp. Not a good design, imo.
 

augiedoggy

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I had this thought too. I'm also slowly building up from a keggle BIAB to a HERMS.

I realized the problem is that would encourage thermal stratification of the mash. The wort sitting idle in the HLT would be boiling hot when the pump kicks on and the you have boiling hot wort in the top of your mash and too cold of wort in the bottom of the mash still.

The pump will keep running until the heat from the wort that just left pump works it's way down to your temp probe. By then, you've probably way overshot the desired average mash temperature because of all the boiling hot wort you just recirculated into the mash.

Even with constant stirring it seems like a guaranteed way to overshoot mash temperatures.
Yup, I thought about this this too but couldnt really find the right way to explain it without a long winded paragraph...
 

Beernik

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I really wanted this idea to work. Because if it did, you could run a HERMS off an STC-1000 and you wouldn't have to worry about cycling burners on and off.

Then it started bugging me that if it was this simple, everyone would be doing it and I had to be overlooking something. After a couple months I realized it's how heat is transferred in the mash tun.

Now you might be able to get this to work by trying to manually maintaining a HLT temp about 5 degrees hotter than your mash tun. That way you aren't working with such a temperature extreme. But it seems like a pain in the butt to do.
 

Beernik

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If you could sufficiently mix the mash so that you weren't overshooting the mash temperature, I don't think denaturing some enzymes in the HEX would be a problem. It wouldn't be any worse than a decoction mash.
 

Beernik

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It looks like he was running his HLT at 80C (176F) and thought 70C (158F) would be better.

Which is basically what I said, it might work if your HLT and MT aren't too far apart (instead of having the HLT at boiling).

It would be a lot like heating your mash in a pot and then putting that pot inside a pot with higher temperature water. The higher temperature water would slightly raise your mash temperature until they even out. After that, the combined thermal mass has to drop in order for the mash temp to drop.
 
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charliebrown52

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Near boiling may have been the wrong wording but like others have said being that hot on the wort is no different from a decoction mash and there is no possible way to have a stuck sparge that's part of the beauty of brew in a bag and as far as step mash go the styles I typically brew would not gain much benefit from different rests especially with the quality of malt these days and again there is no sparge water needed as the entire volume of water is in the mash for biab


As far as burning up the pump I find this very unlikely many people have said they cycle on and off also the ability to set a delay on controler same way you would for refrigerator


As someone else mentioned this would make a super cheap build and would work on the cheap stc1000

http://laramiebrew.club/2014/04/50-herms-system/

That is what I was bashing my design on just switching the hot plate for propane burner and control the pump to cycle as needed I allready hold mash temps ok just not perfect so I could see this not kicking the pump on and off very often at the end during mash out I could recirculated for 10 mins to filter and vorlof
 

augiedoggy

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Near boiling may have been the wrong wording but like others have said being that hot on the wort is no different from a decoction mash and there is no possible way to have a stuck sparge that's part of the beauty of brew in a bag and as far as step mash go the styles I typically brew would not gain much benefit from different rests especially with the quality of malt these days and again there is no sparge water needed as the entire volume of water is in the mash for biab


As far as burning up the pump I find this very unlikely many people have said they cycle on and off also the ability to set a delay on controler same way you would for refrigerator


As someone else mentioned this would make a super cheap build and would work on the cheap stc1000

http://laramiebrew.club/2014/04/50-herms-system/

That is what I was bashing my design on just switching the hot plate for propane burner and control the pump to cycle as needed I allready hold mash temps ok just not perfect so I could see this not kicking the pump on and off very often at the end during mash out I could recirculated for 10 mins to filter and vorlof
The big difference is when controllers are setup to turn motors on such as a temp controller for a fridge they only do it once every couple minutes... not in terms of seconds. Turning it on and off every 10 -30 second would burn up the motor, I am currently doing this with my experimental floatswitch controlled pump but its a $20 pump and I am not expecting a long life..but so far so good. They do make pumps that are designed with a soft start for this..I learned this all the hard way with my wave maker in my reef tank after burning up 4 brushless pumps. The brushed pump motors can just overheat from this. run into it all the time with one of the motors on a uv flatbed machine I service at work. the operator turns the blower motor on and off instead of using the vacuum on/off switch and blows the fuses for the motor this way at least twice a month.

and yes everytime you kick the motor on and off your likely to disturb the grainbed but with BIAB its not likely to plug up.... the other cool thing about brew in the bag is its designed to not need anyof this since you maintian the temps in the pot holding the grainbag directly making all this pointless... just use the pump to reciculate the wort from the bottom of the pot to the top .... why bother with all this?

I say build it and let us know how it works since it seems you had your mind made already...
 

Btaz

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I'm working on a HERMS setup too using propane, but I'm thinking the more traditional constant recirculation method. One thing that I didn't like about the Laramie version is when the pump is off the wort in the tubing is being denatured. Take a look at what I'm thinking in the link. I'm still a thought in progress as in trying to see where I could simplify the setup.
https://www.homebrewtalk.com/f51/herms-planning-2-vessel-propane-single-pump-2-tier-495543/
 

Beernik

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The one I'm working on is also propane.

Right now I'm thinking that when I get to the point of installing a PID, I'll bite the bullet and get Blichmann's Tower of Power controller. I does everything I want. I won't have to convert to low pressure propane. I won't have to install a pilot light. And I don't think I could build the same thing better for less money.

I just don't like the $575 price tag.
 

augiedoggy

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The one I'm working on is also propane.

Right now I'm thinking that when I get to the point of installing a PID, I'll bite the bullet and get Blichmann's Tower of Power controller. I does everything I want. I won't have to convert to low pressure propane. I won't have to install a pilot light. And I don't think I could build the same thing better for less money.

I just don't like the $575 price tag.
What's wrong with electric? You can build a safe 2 pid control panel for under 200 bucks if you have a 220 outlet with CFC even less if its just a 120v rims setupI. Count on $20-30 per heating element and maybe $40 for the wiring and rated plugs for them... (this is the electric section after all) everyone seems to be afraid of wiring a pid up.... there two wires for power, three for the temp sensor and two for the SSR relay (+&-) and one of the element power wires go in one side of the SSR and out the other... very basic,... really
 

Beernik

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What's wrong with electric is brewing in the driveway in the rain.

To go electric in my detached garage would involve paying for another electricial feed from the house so I have 220V there. Plus it involves pipe boring for the conduit or driveway repair after trenching.

To brew in the house would involve giving up a bedroom. And I'm not prepared to do that at this time. Plus I'm not sure I could make everything fit in that tiny room. It's a bedroom in the technical sense that you can fit a twin bed in it.

If I stay in this house, eventually I'm going to install an exhaust fan in the ceiling of the detached garage and brew there.
 
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charliebrown52

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I have ny made up my mind just asking if anyone has actually experience with this it seems like the answer is no everyone seems to have an opinion but no one has attempted my suggestion either



The life of the pump is my biggest concern
But if I get a cheap pump I may try it any way

I like this option because I do want to keep cheap and use the stc if I do decide to go slightly more traditional I will most likely control a hot plate for the hlt with stc as I do not want to add an element to my kettle mostly because I only have access to 120vac power
 

jbaysurfer

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I didn't read all the responses, but it looks like I may be a voice of dissent. I think it would work fine. It would surely not denature any enzymes since the wort passing through the coil would not instantaneously transfer the heat from the "heating vessel" (for lack of a better term), and it would likely only bump up temps a couple degrees as it passes through. It would probably take several full cycles of your mashtun wort volume to achieve even 1 degree of mash temp change, so you could merely check the temp coming off the bottom of the mashtun to know when to have the PID shut it down.

It's also not going to kill your pump either. Those things are workhorses. Sure, if you set your hysteresis at .1 of a degree, it'll cycle constantly, but if your mashtun is insulated it likely is only going to kick on a few times over the course of the mash to maintain temps (at a reasonable hysteresis, like 1-2 degrees), and I turn my pump on and off that many times manually...easily, during a mash.
 

jbaysurfer

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I don't know if you're any good with programming, but I bet it wouldn't be that hard to change the STC-1000+ software so that you could actually program in a full mash profile. You'd have a sabco or tower of power like system for a fraction of the price.
 

Btaz

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There is already a version of stc-1000+ software that can do mashing. Look up black box.
 

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