Dedicated Herms Guide, Problems And Solution Thread

[RustyT]

Sweet thought that may have been the case.

 

[Howlingdog]

I'm not to sure where to put this question but I suppose this thread is closer to the point. I've noticed in European forums - not UK, that most Homebrew systems shown use a stirred mash tun. Since I'm assuming that most of their beers are pilsener/lager and involved decoctions or multiple step mashes this maybe the reason. HERMS/RIMS would eliminate the use of a stirred mash tun but would it be an advantage or a complication?

HD

 

[TheWiggman]

I fly sparge myself because in my case it's simpler. I've only got 1 pump and drain into the kettle at different levels.
2 pumps have the advantage of circulating the HLT, which in your case would be a good idea with that HERMS design. And as above you'll need the 2nd pump for a single tier shebang.

 

[TheWiggman]

I'm not to sure where to put this question but I suppose this thread is closer to the point. I've noticed in European forums - not UK, that most Homebrew systems shown use a stirred mash tun. Since I'm assuming that most of their beers are pilsener/lager and involved decoctions or multiple step mashes this maybe the reason. HERMS/RIMS would eliminate the use of a stirred mash tun but would it be an advantage or a complication?

HD

Minor increase in efficiency I think. And bragging rights. I think it's unnecessarily complicated personally but if you want to pimp your rig it's the next step.

 

[Online Brewing Supplies]

I'm not to sure where to put this question but I suppose this thread is closer to the point. I've noticed in European forums - not UK, that most Homebrew systems shown use a stirred mash tun. Since I'm assuming that most of their beers are pilsener/lager and involved decoctions or multiple step mashes this maybe the reason. HERMS/RIMS would eliminate the use of a stirred mash tun but would it be an advantage or a complication?

HD

HERM-IT is big in Norway, makes sense as they need to keep there mash warm and you dont need to stir.
Nev

 

[mb-squared]

I personally don't like the HERMS coil in the HLT, get it in the smallest water bath you can fit it in.

a herms coil in the HLT can double as an immersion chiller. it's the most economical way to go because it doesn't require a 4th vessel and it can be used to chill your wort. putting your HERMS in a 4th vessel is no where near as economical from this view.

 

[TheWiggman]

I challenge the economy argument mb-squared. I'm plugging Nev again but I did the HERMS-in-the-HLT and later switched to the HERM-IT coil. Item by item, they ended up costing almost the same amount. If I was clever about it I could easily turn the coil into a chiller but I've gone the no-chill path instead for a couple of reasons.
I'd never go back.

 

[QldKev]

Whilst I do brew beer to save some money, I brew beer to make great beer and not to make the cheapest system. I don't like the thermal mass of the HLT for ramping and overshooting so to me setting up a dedicated HERMS is 100% worthwhile. If I built mine again I would like to try either a liebig or shotgun condenser style for the heat exchanger. Then I could use a small pump to pump hot water into it and shut the pump down once I hit my set point.

 

[Burt de Ernie]

Whilst I do brew beer to save some money, I brew beer to make great beer and not to make the cheapest system. I don't like the thermal mass of the HLT for ramping and overshooting so to me setting up a dedicated HERMS is 100% worthwhile. If I built mine again I would like to try either a liebig or shotgun condenser style for the heat exchanger. Then I could use a small pump to pump hot water into it and shut the pump down once I hit my set point.

Kev,

This is exactly how my Rinnai system works!

 

[Beerisyummy]

Hi guys,

I managed to get my new heat exchanger made up this week and have a couple of questions for those that have been doing HX for a while.
Firstly, I ended up making it to fit my kettle/mash tun and run a small HLT with around 1L of liquid to power the whole show. My first wet run with water was good.

Now, my first question relates to mounting the PID probe. The old system just tapped into the return line for readings and I was happy with the results. This time I'm not sure if I can just tap into the line exiting the coil, or if I'll need to use a probe in the bottom of the kettle/mash tun. Anyone have advice on this?

Secondly, can I use glycol in the heat exchanger? Food grade of course.
I ask because I managed to get 40L up to 98c with the rig and the only thing stopping the kettle boiling was the HLT maxing out at 100c+/-. It's not that I will do it as a standard practice, but I'd like to know if it would work before I go chasing some free glycol.

BIY.

 

[Burt de Ernie]

Secondly, can I use glycol in the heat exchanger? Food grade of course.
I ask because I managed to get 40L up to 98c with the rig and the only thing stopping the kettle boiling was the HLT maxing out at 100c+/-. It's not that I will do it as a standard practice, but I'd like to know if it would work before I go chasing some free glycol.

You can use glycol which would mean you have a closed system but my question is what are you using for sparging?....do you have a HLT as well?

 

[Beerisyummy]

No HLT BdE. I just drain the kettle/MT and add more water before cranking up the power again.
Mash efficiency on BS2 is anywhere between 75 to +100%, depending on the grain bill and mash schedule. If anything, I'm trying to dial back the efficiency so sparging isn't a big concern.
I'm doing a 70/30 Wheat/Pils mash tomorrow, so I guess I'll just suck it and see. At least as soon as the bastard starter kicks off. This country air gets pretty cold at night.

Is there another way to bring the boiling point of your HX heating fluid up without making it too corrosive, or adding pressure? I figure 110c would get me boiling in the kettle.

Ahhh! the endless tinkering.....

Edit: I'll try and get some photos if I brew tomorrow.

 

[Burt de Ernie]

Id like to see the pics

 

[booargy]

No HLT BdE. I just drain the kettle/MT and add more water before cranking up the power again.
Mash efficiency on BS2 is anywhere between 75 to +100%, depending on the grain bill and mash schedule. If anything, I'm trying to dial back the efficiency so sparging isn't a big concern.
I'm doing a 70/30 Wheat/Pils mash tomorrow, so I guess I'll just suck it and see. At least as soon as the bastard starter kicks off. This country air gets pretty cold at night.

Is there another way to bring the boiling point of your HX heating fluid up without making it too corrosive, or adding pressure? I figure 110c would get me boiling in the kettle.

Ahhh! the endless tinkering.....

Edit: I'll try and get some photos if I brew tomorrow.

vegetable oil.

 

[dent]

That is a terrible idea. Let's not put a flammable substance with a ****** heat transfer ability on a heating element. All you need is your mash to stick and your shed burns down.

 

[Beerisyummy]

Yep. I might pass on sticking oil in with my cheap kettle element. It's dodgy enough as it is.
Could I just run steam through the HX? Much harder to control I guess.

 

[drifting79]

water is sufficient for heat exhange purposes and its the cleanest alternative , once youve done your brew just drain HX so the elementdoesnt stay emersed !
steer clear of using oils!!

 

[Online Brewing Supplies]

Yep. I might pass on sticking oil in with my cheap kettle element. It's dodgy enough as it is.
Could I just run steam through the HX? Much harder to control I guess.

Dont over complicate a proven simple process, we have done that in the past so you dont have too !

 

[TheWiggman]

I'm on the phone so can't find your old post, but what's your system arrangement? What are you trying to do? I assume you're pumping hot water into a coil and using the coil to heat your vessel. In this case you won't win unless you go the pressurised option or alternative fluids. There are some sciencey reasons why.
Oil is certainly feasible but you have to be careful how you heat it. I think it's a bold path you're going down as it won't be a simple one.

 

[Beerisyummy]

Don't you just hate trying to use a smartphone sometimes.

water is sufficient for heat exhange purposes and its the cleanest alternative , once youve done your brew just drain HX so the elementdoesnt stay emersed !
steer clear of using oils!!

No problems there. I've been using water to heat my mash for several months now and have been happy so far. The question about glycol came about due to my latest arrangement getting the kettle/MT just below boiling without too much trouble. Of course, I couldn't help but wonder if I could easily push it that little bit farther and boil with it.

Dont over complicate a proven simple process, we have done that in the past so you dont have too !

Coming from the man who sells all the complex looking brewery bling! Shame on you. :lol:
After a bit of reading on steam process heating I can definitely see why this method isn't commonly used in homebrew scenarios. Point taken.

I'm on the phone so can't find your old post, but what's your system arrangement? What are you trying to do? I assume you're pumping hot water into a coil and using the coil to heat your vessel. In this case you won't win unless you go the pressurised option or alternative fluids. There are some sciencey reasons why.
Oil is certainly feasible but you have to be careful how you heat it. I think it's a bold path you're going down as it won't be a simple one.

The arrangement started as some copper crammed into a small pot with an element, then I started using the plate chiller hooked up to a LBP for heating water supply and now I've got around 15m of copper coiled around inside the kettle/MT. I figured I'd try using the coil for heating and cooling. So far it seems to do a good job of both.
The kettle/MT runs one of those green pumps with two outlets. One loops back into the kettle/MT and creates a constant whirlpool effect, while the other is used to recirculate through the mash or fill the FV.
Once I've removed the mash part from the kettle I normally turn on the induction plate to boil the wort. I hit 98c yesterday without the induction plate so I figured it was worth investigating a way to boil with the coil. No biggy if it's too difficult.

I'm still undecided about where to get the best temperature reading for the PID? The coil outlet and the wort looked to be within 1c during ramping, although it's hard to say what will happen during an actual brew.

Cheers guys.

Edit: I just found this which is similar to what I'm playing with. http://aussiehomebrewer.com/topic/78352-reverse-herms/ Now to have a read.

 

[TheWiggman]

For all intents and purposes, I think it will be too difficult.

The boiling point of fluids is determined by pressure. Where I am, water boils at 97°C. Once it turns into a gas it bubbles up and then condenses in the air and then will cool very quickly, causing a pocket of air with very high humidity. So essentially, if you are heating water to boiling point then once it boils the liquid state won't exceed your boil temp under atmospheric conditions. Anything hotter becomes a gas and evaporates.
Assuming you have actual boiling water going through the pipe, the stuff that it touches won't exceed the temp of the pipe unless the ambient air is higher than the water boiling point. The liquid in your MLT/kettle will take the heat energy away from the tube, then immediately pass it on to the surrounding air. Hence, the kettle liquid will always be a lower temp than the coil liquid.

So if the hottest you can get in the coil is boiling, and the kettle is less than this, the kettle will never boil without heat from somewhere else.

To address this you can increase the pressure of the water inside the coil to above atmopsheric. This will increase the boiling point, and hence you can make the water hotter than the boiling point at atmospheric pressure. This will then allow you to acheive what you want to do.

This was the 'sciencey' stuff I was referring to.

You could do that, of you could place a gas burner below the kettle and light it with a match. Or (my preference) - insert electric element in liquid, plug into wall, turn on.

 

[Beerisyummy]

"Sciency stuff". I like that.

I'm fine with science behind the idea. Boiling points and such.

I'm now stuck with only a phone, but I'll report back soon on how she goes during a brew.

 

[Beerisyummy]

Just to report back from my experiment.
I tested using a different solution in the boiler to make the kettle boil and I tested the positioning of the temperature probe on my set up. The results were that the coil will happily boil the kettle and the probe worked a treat in the same body of liquid as the heater/ chiller coil.
I decided not to push things too far this first go as I'm not sure how the pump will go with the higher temperatures involved.

There is more info on this in the thread I linked a few posts back. No point in posting the same thing twice.

:beer:

 

[Online Brewing Supplies]

Sorry but KISS.
Nice to see outside the box thinking and tinkering.
Nev

 

[Fat Bastard]

Sorry to butt in on all the innovation goin' on around here, but I want to ask some really base questions about grain crush size and recirculation speed.

Did the second brew on the new rig today, and was less than pleased with some of the antics that went on. On the commissioning brew, I had a slight problem with the grain bed lifting when I changed from recirculate to lauter/sparge settings. When the vacuum momentarily stopped, the grain bed sprang up in the tun and released a lot of what appeared to be trapped air. I occasionally had this problem on the old rig, and it was not a major drama, exceptfor the very small amout of bits of grain that ended up in the kettle.

So, thinking about the issue, i came to the conclusion it was connected to my rather coarse crush of 1.6mm, as reccomended by mashmaster. Righto then. I'll pull the rollers in a bit to 1.2mm and crush it a bit finer and see what happens.

Well, what happens is that you get a grain bed set like concrete and a stalled pump. This occurred during ramp from 52 to 62 and in the ramp to 68. I thought I really stuffed it when the breaker tripped and the HLT/Boil side of my rig shut down, but that turned out to be an amateur gardener cutting through the cord of the electric hedge trimmer, with the electric hedge trimmer. Oh how we larfed!

Anyway, with power restored, and a couple of big handfulls of rice hulls in the mash, the problem went away, got beautiful clear wort and big **** off channels during the lauter & fly sparge. Efficiency was well down too, which I'll put down to the channeling. I've never had channelling in my rig prior to adjusting the grain crush.

I have often heard tell of people crushing to "The Thickess of a Credit Card" which by my verniers and credit card is 0.9mm.

How the hell are these people not getting stuck mashes? Admittedly I don't have the best control of my recirc pump at the moment, but if you cant recirc faster than a Little Brown Pump, why bother spending the dosh on a very nice looking and superb quality Ultimiser pump from a well known site sponsor and contributor and building a special vessel with a custom made element to house one of the same bloke's very nice HERMS coils?

So, how fast do you recirc. and how fine do you crush? In the short term, I'll open the gap out to 1.4 and trial it again with a bag of rice hulls handy, but I'd still be interested in hearing what you're all doing.

Cheers!

FB

 

[Yob]

You only have a LBP fats?

I've upgraded to an 809 but start it off half reduced on the outlet of the pump, when at 63 I open her up, pretty big grist too, no sign of sticking, manifold issues perhaps?

 

[mb-squared]

I run my pump (Chugger) wide open during the whole mash. I just use the factory settings on my Barley Crusher. Never heard of the whole grain bed lifting up. Sounds odd to me.

 

[Fat Bastard]

Nah, running an Ultimiser for mash recirc.

Could run the LBP flat stick without issue at a 1.6 crush no worries at all.

One of the issues with the new rig is that I made the assumption that the speed control would actually work, so I have to throttle it with the three way, which isn't ideal, but works after a fashion.

Problem is, I throttle it back to the same speed as the LBP, which kind of defeats the purpose!

False bottom is the larger diameter Beer Belly one, which served me well in the LBP days. Never seen channelling with it previously.

 

[Fat Bastard]

Some more detail of the grain bed lifting: when crushed at 1.6 with the LBP it would quote often release trapped air during mash out and especially when starting the transfer to the kettle. This would upset the bed and release grain particles to the kettle.

With the big pump, the whole bloody thing lifted to the top of the mash liquor as a single unified mass. No channelling, and only some tiny bits of grain got to the kettle. It sank as the level dropped when the fly sparge stopped and behaved normally.

At the 1.2 crush it stayed put, but channelled like a bastard and was very solid, and I suspect this is the reason for the channels.

 

[dent]

Nah, running an Ultimiser for mash recirc.

I have that same pump. I think you are asking a lot to be running that thing flat out, especially at the start of your mashing regime. I don't think there is much benefit of recirculating much faster than the brown pump goes, unless you have some kind of three phase heat exchanger or something.