Herms Questions

[lokpikn]

OK I am looking at upgrading my brewery to a electric HERMS setup. I will still be using standard ball valves at the moment would like to change to actuators but the cost is out off reach at the moment but looking at a few PID temperature controllers and probes from Auber Instruments in USA. I will be looking at 1 or 2 3600 watt elements that will be ran separately and will have my electrical side beefed up properly to take the load.

I,m sure this will be an on going forum for a while as I'm sure i will have problems and where else better to ask than AHB.

Now for my first question.

I have been looking at quite a few HERMS setups online both here and other sites and there seems to be two main setups for the reticulation of the wort. One is to use your HLT as your main heating source the other is to build a heat exchanger on the side. I have a 50 ltr stainless HLT now if i look at using this to heat my wort its going to take quite a while to increase the temperature of my water in turn the wort flowing through it. Of course i can use less water in the HLT but when it comes time to sparge I wont have enough water at mash out and will slow things down a bit.

The other setup seems to be a small heat exchanger built to the brewery which is the sort of setup i am interested in. My question here is how small can they be i have a mate who can deal with stainless and i was think some stainless tubing about 100 to 150 mm diameter with my 3600w element mounted from below and would only need to heat up say 10 ltrs of water to cover the element. Now this seem like a good idea as i should be able to change temperature of this quantity very easily and quickly. Will this be a problem can you bring you mash temps up to quickly?

I hope this all makes sense to you as i don't know some of the correct terms yet but im sure i will soon. Hope to have this running by xmas would be good.

LOKPIKN

 

[Adamt]

HERMES

Anyway, You'll want a dedicated heat exchanger (HERMS = heat exchanged recirculating mash system) to get better reaction and response times, and to keep things recirculating properly. Your HLT will heat the water to pass through the other side of the heat exchanger to maintain your wort temperature setpoint.

As for sizing it, I think Kirem restored an old heat exchanger recently... search for topics he has created and you should find one about it.

 

[lokpikn]

OPPPS

At least i can still edit the spelling and pretend it never happened.

Now just to remove the above post

 

[Adamt]

It still says Hermes in the title

Now that i think about it, you'd probably just want an element in your heat exchanger to control the temperature on the water in the reservoir instead of pumping HLT water through it, silly me.

 

[Lukes]

A quick google and this bloke has a 2.5 ltr set up.

I have seen paint tins on the net used for herms.

The key to the temp control is the PID

I say go for it.

- Luke



.... heat exchange recirculating mash external system...........

 

[lokpikn]

I cant seem to change the title so looks like spollig is not verys good for me


Thats a good web site looks like its all the go then.

Keen to here form others on there setups.

 

[newguy]

Anyway, You'll want a dedicated heat exchanger (HERMS = heat exchanged recirculating mash system) to get better reaction and response times, and to keep things recirculating properly.

+1

The HERMS I built has an old pot that I butchered to fit the element. It also takes my old counterflow chiller, which I turned into the heat exchanger coil. With the coil installed, it holds 6l of water. You definitely want a small amount of water in the heat exchanger itself. Also go for a separate hot liquor tank that can separately heat your sparge water while you're recirculating the mash.

 

[AndrewQLD]

The smaller the vessel the better. However you will have certain limitations on just how small you can go.
The Smaller your vessel will mean you don't have to have as high a watt element, if your only heating 2 lt of water then a 2.4 watt element is plenty.

I have a 10lt HERMS and only use a 2.4 watt element and I manage to do step temp mashes easily, although it would be more effective if I had a smaller vessel.

The size and length of the copper pipe and the size and shape of the element will determine the size of the herms vessel.

Andrew

 

[Punter]

My heat exchanger is a 10lt SS stockpot with an element pulled from a $10 kettle
and a $5 camping mat wrapped around for insulation.
My MashMate controls the temp and I use my old immersion chiller as the coil.
The first time I used it I wasnt all that thrilled with it. The temps were all over the place.
I realised after a bit of reading over the net that you dont want the flow from the H.E.
going flat out, it only needs to trickle. Now my temps are stable, and I can increase
temp by 1-1.5 degrees a minute.

 

[Linz]

I'm using a 10L urn with a copper, flattened coil.

Let me know if you want to take the big drive up some day...

 

[AUHEAMIC]

My heat exchanger is a 10lt SS stockpot with an element pulled from a $10 kettle
and a $5 camping mat wrapped around for insulation.

Have you been around to my place? I hope its still there when I get home :lol:

 

[Punter]

Have you been around to my place? I hope its still there when I get home :lol:

They do look very similar Peels.
The element in mine is in the same position as yours,
but the copper coil goes under and over the element in mine.

 

[bigholty]

I don't have a HERMS myself, but if you're using an electric-fired heat exchanger, you should should probably match the coil size to the element size, with the amount of water in between acting as a buffer. No point having a massive element in a small pot with small coil, or vice-versa, etc. There's a lot of variables, but the folks on this forum will no-doubt have a good idea what arrangements work best.

:icon_offtopic: Do you get many problems with compaction of the grain bed and slow/stuck run-off in a herms system, given the continuous recirculation?

 

[KHB]

I like the idea of a small pot my question is when circulating your wort what temp do you normally have your HERMS water at??

KHB

 

[Adamt]

The idea of a HERMS is to have a PLC (controller) that will adjust the reservoir temperature (well, turn on and off the element) based on the temperature of wort leaving the heat exchanger, the temperature of the mash, and the setpoint temperature. So you don't actually set the temperature, just the mash temperature you want.

 

[Adamt]

bigh: I'd imagine the liquor is returned to the mash tun via a sparge arm to sprinkle over the mash bed without disturbing.

 

[Linz]

Mine returns thru a manifold below the liquid level....but above the mash bed

 

[Sammus]

I used a 5L camping mat insulated bucket with one of those cheapo kettle elements, worked pretty well. Here's my build thread if your interested.. unfortunately all the pics are gone. A bit of interesting reading perhaps.

 

[lokpikn]

I have been looking at much the same as linz. I will use a copper fed tube placed just under the fluid level so there is no splasing and to prevent the wort from chilling as it passes through the air.

Im still looking at using a large straigt electical element which will be about 300mm long placed in a stainless tube about 150mm diamiter which i guess will hold about 10ltrs of water with some aniled copper tubing runing the whole length of this element. I'm still looking at a 3600w element from a hot water system just in case ii need some real power but as it will be hooked to a PID it will use just enough to get it all to the right temp.

Its amazing how complex some heat exchanges are and some are very simple. As i like the bling factor and to push buttons and stuff mine will be a fancy one(i hope) but im sure it wont make much better beer but just some thing to do as i like this sort of work and also to get the old Grey matter working a swell.


SAMMUS

I have been reading through your thread a few times all ready as there was not very many on this site. Been looking at tonys setup as well very nice indeed.

 

[newguy]

:icon_offtopic: Do you get many problems with compaction of the grain bed and slow/stuck run-off in a herms system, given the continuous recirculation?

The only time mine ever stuck was when I brewed a CAP with a lot of corn and corn starch. But that would have stuck any system. For every other beer I've ever done, I've never had a stuck runoff/recirculation.