HERMS Circulation Issues

[bob1]

Hey guys, I recently upgraded to a keggle HERMS system which does a fantastic job when brewing all grain batches. The issue I'm seeing is when I use adjuncts the grain bed turns into cement and I have to constantly break it up to keep circulation going and temps where they need to be.

I've tried a half pound of rice hulls to help circulation to no avail as well as restricting the flow of wort to keep the grain bed from compacting. Am I missing anything else I can try with my current setup?

To deal with these issue I was thinking about giving up on HERMS and either circulating the HLT water through the wort in a coil or soldering the coil to the outside of the MT and stirring the vessel like a steam jacketed unit. Anyone have any experience or know of any examples of these types of setups?

 

[Yooper]

I've had the same issue- even with slowing down the circulation rate, stirring well, adding tons of rice hulls, etc- the grainbed would compact and create all sorts of problems, including needing to be dumped into a cooler just to unstick the mash. Uggh! I have a bottom draining MLT with a very nice false bottom, but it really clogged up.

My cheap and easy solution was to line my MLT with a bag, like the BIAB folks do. I bought mine from wilserbrew, here on the forum.

The last time I had a brew that compacted again with that bag in there, I was like "oh no!" But all I did was lift the bag from the side, and I heard "glug, glug" so I knew that I had pulled a vacuum. I stirred some more, and that was the end of it.

Most of the time, that doesn't happen (that was the only time in about a year), but I still use the BIAB to line the MLT and haven't had a stuck mash or sparge or even any lautering problems since.

 

[bob1]

I've had the same issue- even with slowing down the circulation rate, stirring well, adding tons of rice hulls, etc- the grainbed would compact and create all sorts of problems, including needing to be dumped into a cooler just to unstick the mash. Uggh! I have a bottom draining MLT with a very nice false bottom, but it really clogged up.

My cheap and easy solution was to line my MLT with a bag, like the BIAB folks do.

Good to know I'm not alone in this! Wouldn't have thought of a solution so simple. I was ready to re-engineer the whole setup. Did you see any issues with efficiency or mashing temp due to some of the wort recirculation bypassing the grain bed?

 

[Yooper]

Good to know I'm not alone in this! Wouldn't have thought of a solution so simple. I was ready to re-engineer the whole setup. Did you see any issues with efficiency or mashing temp due to some of the wort recirculation bypassing the grain bed?

Oh, that's the thing- the wort recirculation does not bypass the grainbed. I recirculate back into it, with the bag not tied or anything. The bag is just lining the works, and not tied or otherwise restricted. I use clips to secure it to the top, but it is very loose in the MLT and not restricted at all.

It could be just because mine is bottom draining, and no matter how I restricted the flow, the grainbed would compact even with tons of rice hulls in some mashes. But simply lining it with the bag meant no stuck mashes, even with gummy wheat and rye and oats.

 

[stratslinger]

I had the same issue one of the first times I ran my HERMS setup - and that was on a no-adjunct beer! I remember breaking up the grain bed, re-vorlaufing, then resuming recirculation at a much slower rate. My last 2 brews had either wheat or a ton of adjuncts (Cream of Three Crops), and I completely forgot to secure any rice hulls ahead of time. A slower recirculation through the HERMS completely avoided any issues even without the hulls. Is it possible you're still recirculating just a bit too quickly on those batches?

 

[bob1]

Oh, that's the thing- the wort recirculation does not bypass the grainbed. I recirculate back into it, with the bag not tied or anything. The bag is just lining the works, and not tied or otherwise restricted. I use clips to secure it to the top, but it is very loose in the MLT and not restricted at all.

It could be just because mine is bottom draining, and no matter how I restricted the flow, the grainbed would compact even with tons of rice hulls in some mashes. But simply lining it with the bag meant no stuck mashes, even with gummy wheat and rye and oats.

My MLT is bottom draining as well, maybe that is part of the issue. I built it that way on purpose after thinking about how easy it would be to drain and clean. A quick rinse after each batch and she's ready for more action.

You aren't using a pico false bottom from AIH are you?

http://www.homebrewing.org/Stainless-Steel-PICO-style-keg-kettle-false-bottom-wsupports_p_1010.html

 

[bob1]

I had the same issue one of the first times I ran my HERMS setup - and that was on a no-adjunct beer! I remember breaking up the grain bed, re-vorlaufing, then resuming recirculation at a much slower rate. My last 2 brews had either wheat or a ton of adjuncts (Cream of Three Crops), and I completely forgot to secure any rice hulls ahead of time. A slower recirculation through the HERMS completely avoided any issues even without the hulls. Is it possible you're still recirculating just a bit too quickly on those batches?

I've tried limiting the circulation with a valve I have on the bottom of the MTL before the pump to no avail. In fact it gets so bad with some of my high adjunct recipes I'm not sure anything would drain into a grant if I had one before the pump. I'm also very sure my pump isn't over powered as its one of those chinese 24v 20$ 1.5 gpm plastic units you see floating around on forums.

 

[Yooper]

I've tried limiting the circulation with a valve I have on the bottom of the MTL before the pump to no avail. In fact it gets so bad with some of my high adjunct recipes I'm not sure anything would drain into a grant if I had one before the pump. I'm also very sure my pump isn't over powered as its one of those chinese 24v 20$ 1.5 gpm plastic units you see floating around on forums.

Remember to never slow circulation before the pump- always after!

But I know what you mean, since it happened to me.

I had two different false bottoms, first the cheap domed bottom from northern brewer. I thought that was the problem, so I got a really nice hinged false bottom, with a stand, from Jaybird. I still had the issue.

Since the bag, no issues at all!

 

[dsniegocki]

+1 to what Yooper is doing with the BIAB bag, I do the same with my MLT and it effectively eliminates any worry of my recirc getting stuck.

 

[bob1]

Remember to never slow circulation before the pump- always after!

But I know what you mean, since it happened to me.

I had two different false bottoms, first the cheap domed bottom from northern brewer. I thought that was the problem, so I got a really nice hinged false bottom, with a stand, from Jaybird. I still had the issue.

Since the bag, no issues at all!

Awesome! You prolly saved me a few hundred trying to figure this out by myself. I'll try the bag and get back with you guys.

Out of curiosity, why not limit circulation before the pump? Any issues besides getting plugged or losing prime?

 

[prrriiide]

Have you considered a slotted manifold instead of a false bottom? I made mine out of copper pipe and used a band saw to cut kerfs about halfway through the tubing. It screws together so I can disassemble it and clean it. Only had one stuck mash with it in 4 years, and that was after I up-sized my system tubing from 3/8 to 1/2.

That said, my MTs are side draining, so it may very well be the bottom drain that's doing it.

Also, when it sticks you can try hooking the inlet of your pump to the HLT and the outlet into the MLT out. Try back-pumping and see if that frees it up. But if it's happening every mash, that's a PITA. Have you looked at your grain crush?

Just a thought...you could use some softer copper tubing that's already in a mostly circular configuration out of the box, and make a circular manifold that would draw wort off from all around the MT instead of from the center. Cap one end and kind of spiral it in to the bottom drain. Drill it full of 3/32" holes and it should give you a good run-off from all parts of the MT.

 

[bob1]

I can always break it up but its just too damn much babysitting for my taste. I set my crush at around .03" which isnt overly fine as some grain just falls through when the mill isnt running.

 

[deprecated]

I had the same problem with my bottom drain HERMs when I first started using it. The solution for my setup was to crush closer to .045" as recommended by Kal over at his Grain Mill page.

When I get to build a system and start brewing again (after having moved a couple of times) I'll use the same .045" for my HERMs and use a BIAB bag as Yooper does for added precaution and easier cleanup.

 

[bob1]

I had the same problem with my bottom drain HERMs when I first started using it. The solution for my setup was to crush closer to .045" as recommended by Kal over at his Grain Mill page.

When I get to build a system and start brewing again (after having moved a couple of times) I'll use the same .045" for my HERMs and use a BIAB bag as Yooper does for added precaution and easier cleanup.

A rougher crush is definitely something worth looking into, but I've run a few batches all grain with no issues so I'm thinking its the adjuncts.

Kal seems like he knows what hes talking about, but he drinks the blitchmann koolaid so I have to take it all with a grain of salt.

 

[Yooper]

Awesome! You prolly saved me a few hundred trying to figure this out by myself. I'll try the bag and get back with you guys.

Out of curiosity, why not limit circulation before the pump? Any issues besides getting plugged or losing prime?

The biggest issue is that the pump will be destroyed. I don't know your pump, as I have two March pumps, but it's been beat into me that you never, ever want to slow the flow TO the pump, as you want it flooded, but instead slow the flow after to the desired speed.

 

[303Dan]

I can always break it up but its just too damn much babysitting for my taste. I set my crush at around .03" which isnt overly fine as some grain just falls through when the mill isnt running.

Just one man's opinion, but .030" seems like a somewhat aggressively fine crush for a recirculating system. I crush at around .043" for my HERMS system and I haven't had any issues at all and still get good efficiency. I've never crushed as fine as you are so I can't say that I know how my system would handle it, but again, in my opinion, trying a less aggressive setting on your mill might be a good idea to try.

 

[devils4ever]

Interesting topic. I've done about 10 batches in my HERMS setup since late last year. I have a SS 8 gal kettle for my MLT with a SS false bottom that sits about 2" above the kettle bottom. My first batch had issues with it getting stuck. I called my LHBS which helped me put together this system and they suggested slowing down the flow rate and stirring the mash. I do both now and have no issues. My flow rate is about 1/4 of full rate.

The stirring also helps keep the entire mash at the same temperature with no hot and cold areas. That said, I would love to not HAVE to stir and have a full flow rate. I will try using the BIAB recommendation and see how it works out.

 

[Thatinfidel]

+1 on the bIAB bag, I used to use no false bottom at all, and only the bag for my 3 vessel system, and always had great results, honestly i'm considering going back to that method, as i don't see much point in cleaning the FB AND the bag for a HERMS system, since the MLT is never subjected to direct heat, the bag seems to do the entire job without the need for a false bottom.

 

[dsniegocki]

+1 on the bIAB bag, I used to use no false bottom at all, and only the bag for my 3 vessel system, and always had great results, honestly i'm considering going back to that method, as i don't see much point in cleaning the FB AND the bag for a HERMS system, since the MLT is never subjected to direct heat, the bag seems to do the entire job without the need for a false bottom.

I'm interested to hear how you manage to drain it? I've replace my full false bottom setup (hose, domed false bottom, etc) with a simple pizza-pan with holes so that the bag has something to drain into, as I also didn't want to have to bother cleaning the additional parts; do you just have the bag in the MLT and only the opening on the bottom side where the valve is?

 

[Thatinfidel]

I'm interested to hear how you manage to drain it? I've replace my full false bottom setup (hose, domed false bottom, etc) with a simple pizza-pan with holes so that the bag has something to drain into, as I also didn't want to have to bother cleaning the additional parts; do you just have the bag in the MLT and only the opening on the bottom side where the valve is?

Draining is handled the same way it would be with a FB.
The bag simply acts as the false bottom. I have a pickup tube, angled slightly off center that sucks up the wort through a ball valve. Once i'm done sparging, I usually still have a somewhat full mlt, so i run that off into a bucket, or pump it straight into a drain. after that the bag is just lifted out, any liquid still in the bag runs off pretty quickly, but i just toss the bag in a 6 gallon bucket, and then empty it into my composter.
Pretty simple really, and no husks or other junk ever make it out of the MLT during the mash and sparge.