RIMS vs HERMS - Electric-specific comparison

In designing my next upgrade, I'm leaning towards HERMS, just because the concept appeals to me. But for those who have gone this route, or who have done RIMS instead, what are the differences you found, as they relate specifically to an electric brewery? Cost to the control panel? Cost of HEX vs RIMS tube? RIMS with one pump to avoid a second pump for recirc in the HLT? What about temp fluctuation or variance in PIDs or RTDs that affected your decisions? Any other reasons you chose to go one way or the other? Again, this is an electric-specific discussion.

I have built both, electric. In terms of cost and temp control capability, they are equal in my mind. They are very precise. More precise than is required. Control of both, is equal as well. You could use one of my HERMS panels and operate a RIMS with it.

On a certain level I see the HEMS as more precise, as you have a big thermal buffer in your HERMS HEX, in a RIMS you have a heating element that is On/OFF with more swings in temp. They are brief and quickly diluted, but the HERMS wort will NEVER EVER get hotter than the HERMS HEX temp.

Temperature ramping will be faster with the RIMS, for obvious reasons, there is no thermal buffer, no thermal mass to change.

Either will allow you to run a two vessel system if you like, which is cool. With a RIMS you could go to one vessel!

In my last system I chose RIMS, before that I used the HERMS. I build my water from RO, so I prefer a RIMS setup, otherwise I am building a huge tank of water in my HLT, to keep my HERMS HEX submerged, that I will not be utilizing for the sparge, you know?

Costs, are equal. Performance, equal. Speed to ramp temp goes to RIMS. Heater temp stability goes to HERMS. I prefer RIMS because it negates the need for a big tank of hot water that I personally dont use.

You could use a SMALL HERMS HEX, if you have a counterflow chiller. Pump HOT water through the counterflow, wort through the other side. Then you could have a VERY small HERMS that would ramp quickly, and the HEX doubles as your chiller after the boil.

Lots of possibilities if you think outside the box. 7 years ago, electric brewing was outside the box

So, electric-wise, it would be pretty much the same? Then either a HEX, or a RIMS tube, would be roughly the same money?

Interesting point on wasting water. I had pictured the HLT volume covering the HEX, but I guess that would depend on the coil placement and length.

Have you observed any efficiency differences in terms of electricity usage?

Further, what about heating the HLT during mash? If going RIMS, would you have to go 50amp? That's one reason I'm leaning towards HERMS. I can recirc, heat my sparge volume, and not have to upgrade my service.

I too have had both... currently I use a rims and find it easier to maintain temps and its quicker responding for sure...
I believe a herms is more costly when you factor in a need to keep the HLT water constantly moving and I find it easier to maintain my mash with the rims while heating my sparge water to 170...

The electric usage would be different, but SO minimal, it isnt worth mentioning, really. The real cost is in the initial heating of the HERMS HEX, which if it is your sparge water, you are doing anyway, right? No added cost.

Either will work well on a 30A circuit, 240VAC. Both will work with less, but I dont like waiting for water to heat.

Rims is pretty easy, pretty fool proof, and needs only one pump. You can build a HERMS HEX water mixer for say $50... you dont need a pump, just a gear motor and impeller.

Both are INFINITELY more efficient than gas.

I've only done HERMS, but I agree with what's being said on the differences, with one exception. The left over water in the HLT isn't wasted as I heat it up further and use it to flush/clean the system.

Cost is negligible, for my last 10 gallon batch I had a long mash time and boiled for 90 mins and my daily itemized electric bill showed about $3 higher compared to days before/after.

BrokenHorn said:

I've only done HERMS, but I agree with what's being said on the differences, with one exception. The left over water in the HLT isn't wasted as I heat it up further and use it to flush/clean the system.

Cost is negligible, for my last 10 gallon batch I had a long mash time and boiled for 90 mins and my daily itemized electric bill showed about $3 higher compared to days before/after.

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$3 every time I brew would add up fast... just saying...

augiedoggy said:

$3 every time I brew would add up fast... just saying...

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Still a good deal cheaper than propane...

MitDaseinBier said:

Still a good deal cheaper than propane...

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Yes it is...although I skipped that stage.
I have a 30a service.... so by switching to a rims setup I am able to run my 1000w rims tube at the same time as either my HLT 4500w heating up sparge water or my BK .... This saves me time as well.. on my old system I had to wait till the mash was done to start stepping up the HLT to sparge temps this was ok when step mashing but I always wanted to give it a full hour at mash temp when doing a single infusion I couldnt do this with my herms plus I never added a recirc pump or stirbar for the HLT so temps would jump drastically when I stired because of hot/coldspots in the HLT.

Herms has advantages too when set up correctly.. just pointing out the benefits for Rims in my setup...

I'm still on the old 3 carbon burner. Will definitely go electric at some point, but that's later on down the line. I find myself lurking and dreaming in the electric section a lot though...

I too have a RIMs and am able to use the RIMs tube to augment the heating of the HLT. I find that the water is always up to temp before I'm done fumbling around with crushing grain. I'd encourage anyone even entertaining electric to make the move sooner than later. I used a turkey fryer twice and decided it sucked. At about that time folks on here started experimenting with electric brewing and history was made. It is such a revolutionary approach to brewing and has many many levels of entry. I was an early adopter of Brewtroller, did a lot of trial and error for them too, but a simple PWM and heat stick can get you started and you can add to it as your system evolves.

I disagree with wasting water on a herms. What is left after sparging I use for system cleaning. As it is filtered water I also use it for sanitizer as my water tends to have a lot of chlorine in it, so it's that much more protection from introducing chlorine into my wort...and it's warm which is much nicer in the winter as I don't much care to freeze my hands with hose water.

If I change my HERMS it will be to go 50 amp so I can use my bk to heat strike water at the same time I'm heating my HLT. That way I can have the HERMS circulating at the correct temp when I mash in instead of waiting for the added cold water to come to temp while my mash is dropping temp.

When I first looked at both RIMS and HERMS when designing my setup, RIMS (in my eyes) had many downsides including:

- The fact that I couldn't run the RIMS element at the same time as the HLT element on a 30A circuit for the size of elements I wanted.
- The (sometimes) non-gentle heating of the wort (as compared to HERMS). This may be a non-issue for some.
- Extra difficulty in cleaning: The extreme heat and use of a hidden/embedded heating element in the RIMS tube requires you to disassemble completely and clean while with my design the HERMS coil is automatically cleaned during sparging. No disassembly required.
- Risk of scorching the wort if the pump was to stop for even a short period of time (seconds), ruining the entire batch.
- Dangers of pressure build up in the RIMS chamber if something was to get clogged. The Blichmann RIMS rocket (for example) has a pressure release valve that will blow if ever a dangerous situation was to present itself but this would in turn spray near-boiling wort all of the place.

HERMS was a better choice for me for my brewing process so I built a design based around HERMS instead of RIMS. You may have different needs/requirements.

Kal

All good points Kal

Well just to be clear I didn't state my theories on why I didn't do or try something.... I gave my opinion based on my actual first hand experience with both...I tried both because opinions and theories vary a LOT here.
IMHO the "issues" above can all be avoided with proper design and use.... Yes the herms is more foolproof but that's because its that much less efficient and has a larger time delay "buffer". They both have possible trade offs.
They both work and do what they were designed for... I'll take the speed and performance of the sports car over the "safety" of the Volvo anyway but as mentioned before, everyone's opinions vary and Volvo makes a good reliable car... I actually just ordered camlock fittings to mount my sensor and element in on both ends of my rims tube but I have been able to clean my rims tube in place with pbw and I see no real reason to believe its not just as clean (or dirty) as the inside of my herms coil was..
Most. People use TC clamps which make it just as easy to pull the rims tube apart so I am not really sure what would make them so hard to clean myself.
My rims tube draws a whopping 3.1 amps btw. And its plenty for 5 and 10 gallon batches with an efficient insulated MT... if I decide to go for form (bling) over function then I may need something bigger.

augiedoggy said:

I have been able to clean my rims tube in place with pbw and I see no real reason to believe its not just as clean (or dirty) as the inside of my herms coil was..

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The intense heat of the element will cause things to bake on and attach a lot more than the non-heated stainless HERMS coil walls.

A good comparison is a boil kettle with an electric heating element: At the end of the boil the heating element has a layer of gunk on it that has to be cleaned/removed (usually by scrubbing) while the stainless walls on the inside of the kettle do not have that same sort of caked on layer and require less cleaning. A RIMS heating element and a HERMS coil are exactly the same sort of comparison.

Kal

kal said:

The intense heat of the element will cause things to bake on and attach a lot more than the non-heated stainless HERMS coil walls.

A good comparison is a boil kettle with an electric heating element: At the end of the boil the heating element has a layer of gunk on it that has to be cleaned/removed (usually by scrubbing) while the stainless walls on the inside of the kettle do not have that same sort of caked on layer and require less cleaning. A RIMS heating element and a HERMS coil are exactly the same sort of comparison.

Kal

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Yes I see what your saying... unlike the surface of my ULWD elements in my kettle my rims element is a brushed stainless so I figured with the wort always in motion around it that it would not have an accumulation. I just received my longer replacement element today so I guess I will find out how bad it is after 4 brew sessions on it now and just pbw cycle rinses...

In any case that is why I have ordered a camlock fitting to easily remove the element for cleaning.

Yup - definitely keep an eye on it at first and clean as needed. You don't want to scorch a batch and ruin it!

Kal

Well I'm eating crow,

I pulled mine apart and found there was a 1 inch area at the very base where it would have been on the other side of the Tee with little or no flow that was totally black and charred.... the rest of the element was surprisingly clean though...
This of course worries me though... I just bought yet another element (17 1/2" long 750w element with a built in thermocouple) I wonder if I can prevent the element from overheating the wort with the built in thermocouple some how? of course it would also make temp control of the wort more complicated and less efficient.
I im also hoping the full 1" stainless rims tube will allow enough circulation inside to where the wort isnt sitting stagnant in that end and allowing any scorching. currently the element was in a section of only 1/2" copper where the threaded adapter was soldered on so it was a tight dead space...

surprisingly I dont really taste any burnt flavors in the three beers I have actually kegged with this rims though...

IMHO, you're always going to have to take a RIMS system apart after each brew to make sure it's clean. It's just one of the things with RIMS. Make it easy to do (no wrenches) and it probably won't be too much work.

Kal

kal said:

The intense heat of the element will cause things to bake on and attach a lot more than the non-heated stainless HERMS coil walls.

A good comparison is a boil kettle with an electric heating element: At the end of the boil the heating element has a layer of gunk on it that has to be cleaned/removed (usually by scrubbing) while the stainless walls on the inside of the kettle do not have that same sort of caked on layer and require less cleaning. A RIMS heating element and a HERMS coil are exactly the same sort of comparison.

Kal

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Kal,
I beg to differ.
First of all, the RIMS tube doesn't require 240V ...I run my 10 Gal system using a RIMS tube with a 4500W ULWD element on 120V , works like a charm and the PID is constantly turning it on and off (almost every second) in response to the minute temp fluxuations of the wort flowing though the tube.

That scenario is entirely different from the BK where I run 240V and continuous current up to 20 amps to get it to temp, and only then do I throttle it down to a continuous 13 amps for the 60 min boil.

I'm sure we all need to clean our BK element nearly every time we use it, but my RIMS element has never needed the same kind of cleaning thats required on the BK element.

Mine was actually clean except at the end where there was no/ little circulation in a tight dead end space. (1" area) So, I believe that either grain or carmelization built up in this area from the lack of flow and caused my contamination/charring... I believe (and hope my larger diameter 1" stainless housing I just ordered the parts for will resolve this but If the 1" camlock fittings work well its cheap insurance and makes it easy to open up and check.

SleepyCreekBrews said:

Kal,
I beg to differ.
First of all, the RIMS time doesn't require 240V ...I run my 10 Gal system using a RIMS tube with a 4500W ULWD element on 120V , works like a charm and the PID is constantly turning it on and off (almost every second) in response to the minute temp fluxuations of the wort flowing though the tube.

That scenario is entirely different from the BK where I run 240V and continuous current up to 20 amps to get it to temp, and only then do I throttle it down to a continuous 13 amps for the 60 min boil.

I'm sure we all need to clean our BK element nearly every time we use it, but my RIMS element has never needed the same kind of cleaning thats required on the BK element.

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curoius what size element is only drawing 20 amps at 100%... all three of my 4500w elements draw between 17.6 and 18.6 amps at full power (240v) and most people say a 5500w draws generally between 22-23amps...

SleepyCreekBrews said:

Kal,
I beg to differ.
First of all, the RIMS time doesn't require 240V ...I run my 10 Gal system using a RIMS tube with a 4500W ULWD element on 120V

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Good point. That's 1/4 the power so it's not as bad.

I'd still recommend taking a look at the innards of the RIMS rube after every brew (at least at first) to see how the system behaves/how often it needs cleaning.

It's important to note too that as long as you don't have any gunk stuck and frying and causing off tastes, you don't need to keep something like a RIMS tube perfectly sanitary as it's all going to be boiled anyway.

Kal

kal said:

Good point. That's 1/4 the power so it's not as bad.

I'd still recommend taking a look at the innards of the RIMS rube after every brew (at least at first) to see how the system behaves/how often it needs cleaning.

It's important to note too that as long as you don't have any gunk stuck and frying and causing off tastes, you don't need to keep something like a RIMS tube perfectly sanitary as it's all going to be boiled anyway.

Kal

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Darn good advise.

augiedoggy said:

curoius what size element is only drawing 20 amps at 100%... all three of my 4500w elements draw between 17.6 and 18.6 amps at full power (240v) and most people say a 5500w draws generally between 22-23amps...

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It's a 5400 watt wavy element ...I think it'll draw more than 20 but I just stop there as a matter of habit (my old analog gauge was 0-20 amps)

kal said:

IMHO, you're always going to have to take a RIMS system apart after each brew to make sure it's clean. It's just one of the things with RIMS. Make it easy to do (no wrenches) and it probably won't be too much work.

Kal

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I wouldn't let any element that touched wort go a brew without a cleanup at the end of the brew day. That is one of the nice things about a herms, don't need to worry about the HLT element.

I chose to go from turkey fryer propane to 5500W RIMS. I thought the HERMS was extra piping, extra pump, extra vessel, and with really hard well water I brew with RO (which becomes in short supply on brew day) less water use. Though I've often wondered if brewing with raw well water would magically produce some kind of beer nectar, I haven't tried it. My main concern in researching the RIMS approach was about how hot the element gets in the tube and scorching. I found many references and anecdotes that suggested that would be really unlikely. In fact, the bare element in the BK probably runs more risk of "scorching" than the RIMS tube - assuming you keep a decent flow runnning. I admit that I had some issues with sparge arm design and had one clog that stopped flow, and there was what I would describe as a "steam bubble" event that lasted a fraction of a second with no ill effect relative to burning flavors. I started over on the sparge arm design and its not going to clog again.

I run with two vessels and add water directly from the RO tank with a solenoid valve that supplies a threeway valve to add water to the recirc as necessary and get to the final boil volume by the time its done. It seems less complicated, super responsive to temp control, super accurate, and easy to clean with a TC RIMS tube that disassembles. Both the BK and RIMS elements have the same amount of gunk on at the end of the day. Cleaning up is something to do while staring at the BK between additions. By the time the boil is ready to chill, the other side gear is drying in the sink.

RIMS seems to have the edge (slight) in my opinion and my situation.


Sent from my iPad using Home Brew

Wel... I've changed my mind completely on this. Two scorched worts in a row. Grrr. So, I made a low budget adaptation to HERMS with a couple 5gal plastic buckets that were laying around, some 1/2 cpvc pipe and a cheap tan recirc pump. I still used the RIMS tube as the heating element, but moved the temp probe into the mash tun. Retrained the PID. And the immersion chiller now does double duty as the heat exchanger tubing and the usual immersion chiller at the end. Went super smooth. Will post some pics later.


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Decoy said:

Wel... I've changed my mind completely on this. Two scorched worts in a row. Grrr. So, I made a low budget adaptation to HERMS with a couple 5gal plastic buckets that were laying around, some 1/2 cpvc pipe and a cheap tan recirc pump. I still used the RIMS tube as the heating element, but moved the temp probe into the mash tun. Retrained the PID. And the immersion chiller now does double duty as the heat exchanger tubing and the usual immersion chiller at the end. Went super smooth. Will post some pics later.


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I'd love to see those pics.

While a well designed RIMS setup shouldn't scorch wort (Sabco's been doing RIMS for years), the risk is always there - especially if the flow fails for whatever reason, including the operator turning off the pump.

You really need to interlock the heating element and the pump to ensure that if for any reason the pump (flow) stops, the heating element turns off immediately.

Kal

I did what Kal mentioned above.

UPDATE... so My second rims build has about 10 brew sessions on it now and the only time the element had any buildup on it whatsoever (more of a slight discolored light coating) was when I made the mistake of leaving the element on while closing the flow valve and shutting off the pump... this cleaned right off and was far from the type of normal buildup I see on the Boil kettle element bt still it scared me so I added a flow switch for $10 to my rims circuit which works awesome to shut off the rims element if the slow ever drops dramatically or shuts off...
so far besides that one time all I have needed to do is rinse the rims with hot water after brewing and its stayed completely clean... the other nice thing is if it does need cleaning or inspection I just open the camlock fitting to do so..

Kal is correct. That's what was happening to me. Flow would get to slow - or even stop - and pfft. One time the steam bubble created enough pressure to pop the silicone tube off the cam fitting and sprayed hot wort all over the ... well, you get the idea.

I want to keep in simple - I don't think there's a need for an flow sensing interlock with HERMS because a) a problem is less likely, and b) it would be very slow to develop.

Anyway. Here's the pics. I cut the top and bottom off a sheetrock compound bucket to make an insert, pop riveted the CPVC pipe and fittings to it and slid it into the pickle bucket full of tap water. Hooked it up with the immersion chiller, PID, etc. - and it works. Someday I can upgrade the vessel, go stainless. But this got me doing HERMS - quickly, simply, cheaply, and I feel safer!

Decoy said:

Kal is correct. That's what was happening to me. Flow would get to slow - or even stop - and pfft. One time the steam bubble created enough pressure to pop the silicone tube off the cam fitting and sprayed hot wort all over the ... well, you get the idea.

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That's actually a good thing - the alternative could have been an exploding RIMS tube with chunks of stainless. The Blichmann RIMS rocket has a plug that's meant to blow out exactly for this reason. Sprayed hot wort is better than chunks of steel!

Kal

Im not really sure I follow the steam bubble issue... If the inlet and outlets are orientated correctly so all the air is pushed out how does a steam bubble occur? also what stops the pressure from just escaping out of either open end of the rims tube? are we talking about some hypothetical situation where there would be two closed ball valves at each end of the rims tube? how else could such pressure reach that point? Even if the the valves were closed the temp sensor correctly located at the exit outlet end of the rims would reach a hot enough temp to turn off the element? or are we assuming all these things where not taken into consideration and it was designed incorrectly?

augiedoggy said:

Im not really sure I follow the steam bubble issue...

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A steam bubble is a bubble of steam - easily created in a RIMS tube when the wort starts to boil inside.

But I agree - unless you had ball valves on both ends of your tube - which is a really bad idea BTW - it's highly unlikely that a RIMS tube would explode. In my system, the success of the system being scorch free has hinged on the false bottom.

Correct - Blichmann includes the release valve on their RIMS rocket just in case something gets clogged and may cause an unsafe pressure buildup.

Kal

atoughram said:

A steam bubble is a bubble of steam - easily created in a RIMS tube when the wort starts to boil inside.

But I agree - unless you had ball valves on both ends of your tube - which is a really bad idea BTW - it's highly unlikely that a RIMS tube would explode. In my system, the success of the system being scorch free has hinged on the false bottom.

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yes like a pot of water boiling with the lid on it creating a boilover condition and lifting the lid, I get it... what I dont get is why it wouldnt escape out the top (or bottom) of the rims tube... Your temp control should prevent anything from getting that hot in the rims tube in the first place. a whole lot of what ifs and mistakes have to happen for this to be a problem from what I see...
Its kind of a non issue for me since I filter the solids from my wort in my MT before the reach the rims tube. I need to do this or my small pumps would clog up.

atoughram said:

the success of the system being scorch free has hinged on the false bottom.

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OR things like the watt density and proper control of the flow and temps...
the watt density of my 25" element is very low causing it to heat the wort in a similar manner as a herms only with faster ramping rates since there is no body of liquid to heat up in order to transfer the energy to the wort indirectly....