HERMS vs. RIMS (electric) Pros and Cons

[caskconditioned]

This is exactly why I went to the trouble of having mine enter and exit through the side of the keg. PBW recirc, water rinse, gravity drain + air for good measure.

Ahhh, grasshopper! Very smart.

Don't mean to hijack this thread...From your pics it looks like you have a probe in the HERMS chamber as well as on the "out" side; is that correct? Do you mash-in via the HERMS or bypass it? Are you doing anything to stir/agitate the water?

 

[Bigscience]

Ahhh, grasshopper! Very smart.

Don't mean to hijack this thread...From your pics it looks like you have a probe in the HERMS chamber as well as on the "out" side; is that correct? Do you mash-in via the HERMS or bypass it? Are you doing anything to stir/agitate the water?

I'm not sure I follow you. I have a probe on the out flow of the MLT, one in the chamber to regulate the HEX via PID and another one on the out flow to see what the return temp is.

For dough in, I heat strike water in the HLT and drain the desired amount into the MLT and then add grain and mix. After it's well mixed, I start to slowly recirculate to hold the temp. I recirc the whole time.

I don't do any stirring for now. I did some initial tests to see if it made any difference and it did help the outflow temp to be a little higher but only when there was a larger differential to begin with. It also dropped the HEX temp. For maintaining a mash temp or even for mashout/ramps, I just turn up the HEX temp. I know there are other people who use a air pump to stir up the water but it seems like that could actually be robbing heat from the system. If I do go with a mixing system, I'd go with an overhead stirrer.

 

[caskconditioned]

I'm not sure I follow you. I have a probe on the out flow of the MLT, one in the chamber to regulate the HEX via PID and another one on the out flow to see what the return temp is.

Gotcha... I (currently) take the reading on the out flow and that's what the PID uses to turn the heating element on/off. When I built it a few years ago I thought it would be better since the out flow temp is really what's important. But on my new build I'm planning on doing something similar to what you have and incorporating a BCS controller. I think knowing both the chamber and out flow temps is better.

 

[klyph]

Gotcha... I (currently) take the reading on the out flow and that's what the PID uses to turn the heating element on/off. When I built it a few years ago I thought it would be better since the out flow temp is really what's important. But on my new build I'm planning on doing something similar to what you have and incorporating a BCS controller. I think knowing both the chamber and out flow temps is better.

Having the PID probe in the HLT is the way to go. In the event of a stuck sparge/pump failure, measuring the HEX output could lead to a massive overshoot in the HLT.

 

[slakwhere]

i'm in the process of building my first sculpture and chose to go hex over rims, mostly because i already had the IC, it's nearly impossible to scortch (rumor or not), and i can work it as a manual system until i get the automation in place.

 

[zymurgy101]

I'm sure it is a newbie question, but why are we not including direct fire RIMS in the discussion?

 

[Bobby_M]

There really is no particular reason. I guess it's because I already use a direct fire RIMS (manual mode) so I was thinking towards the future and picked the two most common alternatives. I'll start.

Direct Fire RIMS:
Pro:
Shortest recirculation path (little to no impact though).
Fastest heat steps.

Con:
Stuck recirculation for too long will scorch, no question.
Automating harder than electric options (pilot lights, etc).
Requires full false bottom to keep thick mash off heatable surface.
Requires heat resistant insulation on tun.

 

[klyph]

I'm sure it is a newbie question, but why are we not including direct fire RIMS in the discussion?

Well, he did say electric in the title.

 

[Cape Brewing]

HERMS:


Cons
•mostly useless for step mashes or adjusting mash temp, unless you use a vessel other than HLT or overshoot sparge temps

NOT arguing... just saying that I do just what you've suggested and use a third vessel... my boil kettle for my HERMS system.

I heat my HLT to a few degrees over my mash temp and then heat my boil kettle to my strike temp (plus a couple degrees for loss in transfer).

To mash in, I fill the MT from the BK and then just circ through the HLT.

If I want to do steps, I simple shut off the circ through the HLT for a few minutes, bring the temp up in the HLT... I do a small infusion from the BK and then circ through the HLT to finish off the step. It can be done very quickly (five minutes) if done right and you don't end up with a million gallons in the MT.

I think adjustments are easy on my HERMS... too low I just bump up temp in my HLT and for small adjustments it doesn't take long. For big adjustments, again, I'll just do a small infusion along with raising the temp in the HLT.

For downward adjustments... that's easy... jsut add a small amount of cold water to the HLT and it'll drop the mash temp quickly.

 

[hatfieldenator]

There really is no particular reason. I guess it's because I already use a direct fire RIMS (manual mode) so I was thinking towards the future and picked the two most common alternatives. I'll start.

Direct Fire RIMS:
Pro:
Shortest recirculation path (little to no impact though).
Fastest heat steps.

Con:
Stuck recirculation for too long will scorch, no question.
Automating harder than electric options (pilot lights, etc).
Requires full false bottom to keep thick mash off heatable surface.
Requires heat resistant insulation on tun.

Okay, newbie help here...So, if I were to have this sort of set up (http://www.brew-magic.com/rims_brwy_classic.html) and wanted to do step mashes manually, my biggests risks would be that the recirculating wort could become a stuck mash and cause scorching? (how often does this happen if you have a good false bottom?) Is heat resistant insulation absolutely necessary (couldn't you just keep your burner turned on low enough to maintain the temps)? Would the above system work well without any modifications if I'm interested in doing step mashes in the future?

 

[zymurgy101]

Well, he did say electric in the title.

Yea, I was just curious why he specified electric; it seemed like too good of a thread not to have all info compiled in one place.

 

[Bobby_M]

Yea, I was just curious why he specified electric; it seemed like too good of a thread not to have all info compiled in one place.

It was just my short-sighted scope is all. Everyone should feel free to inject any mash maintenance system and list its pros and cons (in context with the alternatives).

 

[Bobby_M]

Okay, newbie help here...So, if I were to have this sort of set up (http://www.brew-magic.com/rims_brwy_classic.html) and wanted to do step mashes manually, my biggests risks would be that the recirculating wort could become a stuck mash and cause scorching? (how often does this happen if you have a good false bottom?) Is heat resistant insulation absolutely necessary (couldn't you just keep your burner turned on low enough to maintain the temps)? Would the above system work well without any modifications if I'm interested in doing step mashes in the future?

I do this right now on my system. I don't think I'd walk away from the system for too long because I have on occasion lost recirculation. In most cases it's because I'm running it really slowly with the ball valve cranked down and some of the grain particles collect there and block it up. I've since learned to run the recirculation a bit faster at first to clear out the grain, then slow it down. My opinion of this type of system is likely tarnished due to my burner not being adjustable enough so take it with a grain of salt.

Keeping the burner low to keep from scorching or overheating is sort of at odds with no insulation when ambient temps are low. My garage is like 45F in the winter and a bare tun loses a lot of heat.

 

[Bigscience]

Anybody out there do a 4 chamber direct fire with a heated grant? It seems you could pull it off with a thinner mash and if you weren't directly pumping against the grain bed, you could eliminate a stuck mash. This would also allow the use of a cooler or a fully insulated MLT. Just a thought.

 

[Sizz]

Can we argue now?

I think you guys covered everything. I'd argue scorching is not an issue with an electric RIMS with PID control. HERMS is stratification proof although I'm not sure how significant stratification is with a RIMS. There's significant velocity and turbulence in the heating path.

Stepping is the primary advantage of RIMS. Nearly all of the power is getting into what you are trying to heat up, and not a separate vessel with a much larger thermal mass.

Instant water heater mode for RIMS is nice. It also cleans itself during the sparge. And you don't need an HLT, so less stuff to clean and a smaller brew rig footprint.

 

[hatfieldenator]

I recently purchased a used HERMS system and can testify that step mashing is not a problem with a large enough heating element. My system has a 5500 watt element in a 11.5 gallon keg (that is usually only full of about 8 or 9 gallons of water during the mash)I can do 10-15 degree increases in temperature in about 3-5 minutes depending on how fast the recirculation is running. I don't know if this is too slow for step mashing? Seems it would work well to me.

 

[Sizz]

It's a grey area for sure. The effects of mash temperatures is well documented, allowing us design a beer and replicate it. We're doing our best to achieve that target temperature as soon as possible. Ramping, which is really what we're doing, adds ambiguity. Are there discernible differences in the final product when you ramp over a 5, 10, 15, X, period? I haven't found any studies on this. I'd guessing there would be differences when ramping from a protein rest to sacc over 5mins vs 30min, especially if you had a high (155+) target temp. I went from single infusion to RIMS stepping so I can't say myself. Repeatability is probably more important.

 

[Cape Brewing]

Wow, thats gotta be the least confrontational post i have ever seen on the topic (standing and starting a slow-clap).

As someone who has been using a 45 gal herms system for a while now.... And as i was saying a bit earlier on this thread, you CAN step on a herms system, but here is my little addition, you need to reeeeaaly know your system.

You need to know how quickly your heating element will bring up the temp in your mash How many btu's is your hlt-heater throwing out? How efficient is your heat exchanger? How quickly can you raise the temp of any possible infusions? Etc.

It CAN be done and done reasonably easily but you need to really know your particular system.

 

[pnh2atl]

As someone who has been using a 45 gal herms system for a while now....

Is there a max size mash for either of them? We are looking at a nano system and where leaning towards a HERMS. I like the idea of a stand alone vessel for the HERMS system and I think I might incorporate that into ours. That provides a lot of flexibility, but does it provide any up side to a larger mash? Is a 1.5 bbl or a 2 bbl system to big for either?

That is all..........

 

[Sawdustguy]

I am a RIMS brewer and I think there is too much emphasis being put on "step mashing". I have been brewing for a while and have yet had to do anything more than a single infusion mash. I have made many batches where it called out for an undermodified malt and was able to find the same type of malt that was fully modified. I wonder how many homebrewers ask for a malt analysis sheet when purchasing malt? The only exception to this was a wheat beer where I could not find an equivalent malt that was fully modified and decided to pick a slightly different substitute. Almost all domestic malts are fully modified. There are some who think it is cool or sounds good to say that they step mash when in reality if a fully modified malt is stepped the final result has been stripped of the body it could have had if a single infusion was used. If you don't believe me just read Palmer or some of the other experts. HERMS users fear not, step mashing is something you may never have to do.

 

[Cape Brewing]

I wouldn't say "never" at all... yeah, I totally agree that with today's modified malts, steps aren't the necessity they used to be but I always step my mashes that contain any significant amount of wheat. I have been doing beta glucan rests at about 100 just to keep the mash fluid and then, since I'm already down that path, I'll do a protein rest as well.

I don't do a ton of them but I wouldn't say "never" at all.


And pnh2atl... I'm not sure I understnad your question 100%.... are you asking if RIMS and HERMS systems, by their nature, are "better": for large batches?

No expert at all but I would think they would have the advantage of eliminating the stratification of temp in the mash... and the larger the mash volume, the more stratification I would think you would get.... so... my theory would be that these two systems would be better suited for larger batches.

 

[pnh2atl]

I was wondering if at some point a batch gets to big for either. Or is one is better for large batches 2bbl plus lets say.

 

[dutch101st]

I just did a complete overhaul/rebuild of my operation:

https://www.homebrewtalk.com/f11/its-done-testing-commence-tomorrow-198694/

I decided to go HERMS soley because of the scorch wort risk and my inability to do anything with electrical other than lighting myself up (mans gotta know his limits)...so building a PID was out of the question.

ALthough I do like the RIMS approach as well...

Well, leave it to me to change my mind...I am going to go with a RIMS for a while...will see how it goes. I didn't really like how my HERMS turned out, but now I am going to be able to do both here soon.

New control panel and doing PID/Temp control the way it should be done.

 

[maztec]

With my tendency to burn things, I have been using HERMS to some degree. I have a two pot system and have been using the BK as an HLT. Of course, this presents some problems, like where to poor the liquid off to. As a result, I've been using my mixing bucket as a storage vessel, but I really do not like filling a plastic bucket with hot water. Oh yes, and I am all electric.

I have been working on improving that setup for the last few months, including changing all my fittings out to tri-clamps and adding a third bucket to the batch. However, for some reason, my mind just can't let go of using my BK as an HLT and just using my HLT as a storage vessel. Although, I think I have been convincing myself not to do that with my rebuild.

I bring all of this up to throw the combined CFC HERMS + RIMS into the mix of options here. What I am looking at doing is as follows:

* CFC between HLT and MT, two pumps, circulate both past each other.
* Depending on the rate at which the system can step up, I may add a RIMS after the CFC going back to the MT, so the RIMS is doing minimal work to increase the wort temp that last few degrees. Alternatively, I could put it before, but it seems like I would have to guess at what temp rise I could get out of the CFC and then have the RIMS raise to just before that, so after just seems simpler because I can test the temperature between the CFC and RIMS and after the RIMS and have the RIMS heat accordingly.
* All else fails, use the BK to bring an extra gallon or two up and toss it in to raise the mash temperature faster, but I doubt that would be necessary.

I know, overkill, at that point I probably should have gone to steam, but steam and pressure scare me.

So, other than the overkill and cost, I am sure someone can tell me why this is a dumb idea.

Keep in mind, I am still thinking about it, my first step here is to update my pots and go to a full three vessel setup with CFC HERMS. Then to add the RIMS as necessary.

 

[skepace]

Interesting posts and thank you to all that have. I am in the process of having to choose RIMS or HERMS. Building an electric system is something I think I am going to do.

Thanks for all of the information.

 

[Ozarks Mountain Brewery]

Ive been using rims for years, only recently I changed my rig design and began scorching grain over and over from the poor pid settings and constant stuck sparge and pump cavitation, Ive always liked it using the rims in a simple brew in a bag set up but a big 25 gallon 3 pot system is not working for me, im tired of constantly having to watch it and baby it so

rims pros: its easy to brew anything for a small set up and a low wattage element, easy to set up and easy to clean with Bobby's try clover set up

rims cons: you have to keep it clean, the element will sour easy setting for a week, you have to have a good handle on your pid range which is hard to do and it will scorch if you have a stuck sparge or the pump losses prime which makes you stand in front of it almost the whole mash

 

[Sleepyemt]

What's the thickest mash you'd go with either system? Currently looking into both...

 

[Ozarks Mountain Brewery]

with any recirculation system its the same, and to each brewer it may be different, I generally go by 1.5 to 1.6 qt/lb, but this year I don't even measure the water I let the grain settle and soak up then go by 1.5 inches of water over the grain after recirculating through the hoses and rims coil, that allows it to raise or lower some without going below the grain level when recirculating

 

[headfullahops]

I mash in what used to be my boil kettle to which I added a false bottom and recirculation/sparge arm (Bobby's Locline model). I currently use direct fire to heat strike water in it and to manually maintain mash temps, which is quite a PITA as you may imagine. I have a Hop Rocket that I bought a RIMS conversion for and am looking at sourcing a PID controller. I plan on using RIMS primarily to maintain mash rest temps and using direct fire to raise mash temps (I don't usually step mash, per se, but I do take it up to 168 for mash out). Not that it's the end-all-be-all of brew systems, but that's how the Sabco Brew Magic operates, from what I've seen.

I'm presuming that, since the RIMS won't be used for the purpose of raising the entire mash temp, only maintaining rest temp, I shouldn't be in any danger of scorching in the tube. Of course, recirculation flow could potentially slow or stop, but I think the controller I'm looking at has contingencies built in for that. Besides, I haven't had any issues with recirculation flow since making everything in the recirculation path high flow (thanks again to Bobby). Having said that, I'm sure to have complete blockage on my next brew.

Cheers!

 

[jimboh]

Old post I know but been resurrected at least once and I would like opinions.
I am perhaps not as much a perfectionist as many and I have used a Grainfather before moving on to an The ElectricBrewery copy. I liked the simplicity of the GF and was happy with the brews but wanted bigger batches. I found the Electric brewery made great beer but took much longer on brewday.
So I built a system similar to the brewha 3in1 except I used a single 20G kettle with 5500w element and a Breha SS colander (rather than a BIAB bag). I have a separate hlt with a 3kW element for sparge water (converted corny keg with 2"sanke that can double as a base for a still) . I recirculate during mash and use CraftbeerPi rather than pids to control temp which during mash is with a sensor in recirc flow. Element power is controlled by the computer software using PWM, which for those not in the know means pulsing the element to deliver much lower heating power. Maintaining mash temp the element is typically run at 10-15% power (equiv to 550w maybe?) but maybe as low as 4 or 5 % . The bottom of the colander (perforated SS) is around 1" above the element so I am hoping there is little chance of scorching. I have only brewed once, two days ago and mash temp was held constant. I also have temp sensor in the wall of the kettle and that was typically showing a degree or 2 higher than the recirc temp. My efficiency on Beersmith came out at 78 -79% (I had a spill and lost a couple of litres). Its a new recipe stout with choc malt and roasted barley so I doubt I will be able to tell if there is any scorching. Is this a viable alternative to RIMs or HERMs or only for those who like me are not that perfectionist?

CraftbeerPi based controller with pwm used to control a RIMS heater may be a great way of reduding risk of scorching.