RIMS HERMS Hybrid Using CFC

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thekraken

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Does any one use there CFC double duty to maintain mash temps as well as cool?

I'm in the middle of rebuilding my little system. Here is the progression of what I've done so far and what I'm thinking:
  • I had been using a 1,375 watt RIMS tube to control my mash
  • I just picked up one of these fancy all copper ZChiller's with the convoluted inner tube (counter flow chiller) because I was tired of my DIY immersion chiller
  • I have a handful of these cheap DC tan pumps sitting around.. so extra pumps
  • I've already just installed 240v service in the garage because I'm working on an electric kettle

So, here is what I'm thinking: Why not use the CFC as a HERMS as well as a chiller? I'm thinking of reusing the RIMS tube as the heat source for the CFC. The RIMS has a 5500 watt element in it so I'd rewire it for 240v. Id recirculate a small amount of heating water for the RIMS tube in my old dusty kettle from extract days.

I can't help but think I'm just over complicating things but I also think there could be some advantages here. I'm wondering if with the 240v RIMS tube as the heat source through the CFC if I could ramp temps quicker than with either a standard HERMS/HLT or with my 120v RIMS directly inline with the wort? I think back to brewhardware bobby's youtube video showing him using a 5500 watt RIMS tube for on demand sparge water.

I'll also have the benefit of knowing that I wont scorch my wort, not that I have ever scorched my wort with my 120v RIMS. (but there was always the possibility) Given that I haven't had scorching issues this only matters if my first assumption that ramping will be quicker turns out to be true.

Also, my RIMS tube is an old school DIY screwed together out of a bunch of SS pipe fittings, if I'm only ever running water through it now I don't have to worry about taking it apart and cleaning it any more.

Thoughts?

For reference:
CFC: https://www.zchillers.com/product/large-zchiller/
Bobby's on demand sparge water: [ame]https://www.youtube.com/watch?v=0AGUOCeM-WU&t=160s[/ame]
 
I have been thinking the same thing as I do not want the expense of a dedicated herms fitted HLT. I was looking at using a Jaded chiller to do the same thing. It would allow the chiller to do two things on brew day.
 
I have been thinking the same thing as I do not want the expense of a dedicated herms fitted HLT. I was looking at using a Jaded chiller to do the same thing. It would allow the chiller to do two things on brew day.

Using one of Jaded's ICs or their cleanable counter flow?
 
Most likely a cleanable counterflow. I have a stainless IC and I am not real happy with its performance. I also have a Blichmann Therminator and while very fast at chilling it is a pain to clean.
 
I don't see the need to use your CFC as an intermediate heat exchanger. To me it adds unnecessary complexity. Let the RIMS do its job. If you are looking for increased heating, make sure your flow is good and adjust power as needed. I use a 5500W element in my RIMS tube and it's powered in a dual voltage setup like Bobby's. I use 5500W for mash water heating, mashing out, and on-demand sparse water heating. I run it at 120V / ~1350W for mashing including step mashes. I haven't burned any wort yet, but again, ensuring adequate recirx flow is key.
 
I don't see the need to use your CFC as an intermediate heat exchanger. To me it adds unnecessary complexity. Let the RIMS do its job. If you are looking for increased heating, make sure your flow is good and adjust power as needed. I use a 5500W element in my RIMS tube and it's powered in a dual voltage setup like Bobby's. I use 5500W for mash water heating, mashing out, and on-demand sparse water heating. I run it at 120V / ~1350W for mashing including step mashes.
I hear ya. The more I think about it it doesn't really add much complexity, it's at least no more complicated than a HERMS.

I haven't burned any wort yet, but again, ensuring adequate recirx flow is key.
Me neither, but I currently use a plastic flow meter (non food rated) that automatically shuts off my RIMS tube if it measures too little flow. This has saved me more than once when I turned around and had a stuck mash. At least this way I could get that piece plastic out of my wort's line and not worry about burning... or non food rated plastic...

I already have everything I need sitting around... now that I have this stuck in my head I'll run some temperature control tests sometime and see if I can't get some hard data on ramping speeds.
 
I'll put this here for safe keeping:
MdtVWiO.png
 
Using a CFC for RIMS is an excellent idea. You have way better temperature control and can ramp way, way faster.

With a conventional HERMS, the ramp speed is limited by how fast you can raise the temp of the HLT and the mash at the same time ! Or, if you run the HLT much hotter than the mash, you need to stop circulating or bypass the HLT coil when you reach the target mash temp.

If you use a CFC as a RIMS HX, you can run the HLT at whatever temp you want (175F ?) and then only recirculate the HLT water when you need to add heat to the mash. And you can vary how much heat you are adding by controlling the HLT pump speed.

I have no idea why more people don't use their CFC as a RIMS HX.

I also have no idea why people put SS HERMS coils in their HLT. Copper has way, way better thermal conductivity. And it is cheaper and easier to work with.

Some people will say that you need an extra pump to circulate the HLT water if you use the CFC as a RIMS HX. The truth of the matter is that you need a pump to circulate HLT water if you use a HERMS coil anyway. HERMS coils are very ineffective if the water isn't moving past the coil.

There is also a variation on this wherein a HX coil is inserted into a very small hot water bath heated by an element. This was pioneered by the late Paul Wicksteed, on his Time4Another1 Youtube channel. https://www.youtube.com/user/Time4Another1

There is yet another variation of this wherein the CFC coil is used with steam. I set up a system to do this but abandoned it due to the safety concerns of working with steam.
 
You can ramp faster than HERMS with this method, but not faster than normal RIMS. With RIMS, all of the power generated goes into the mash. With an intermediate heat exchanger, you will not be able to transfer all of the heat. As the CFC's transfer inefficiency increases, you would approach a limit of the boiling temperature of the RIMS water, and then you couldn't add any more heat. That said, the copper CFC probably has pretty good transfer efficiency.

And that that said, it will ramp fast, and fast is probably fast enough. No doubt it is a better solution than HERMS, which personally I think is a foolish and outdated technique altogether. But what do you gain besides complexity? Why not just use high power RIMS? Ensure the recirculation rate supports the heat you are adding. With that flowmeter and modern controls, you could easily set a heat amount commensurate with the flow. Or let the PID do the work (with proper tuning). As I said, I mash out with 5500W RIMS heat at full power - and raise 7+ gallons of mass in under 10 minutes from ~152 to 170 degrees.

As unpopular as this sentiment is... I would also say that copper is a good route to go. I am trying to eliminate all copper because I believe Cu toxicity is a real possibility (elevated temperatures, lower pH, leftover corrosion), and I want to move toward LODO, which we confidently believe is a no-no. I currently use a Cu CFC, but its going away soon.
 
I hear ya. The more I think about it it doesn't really add much complexity, it's at least no more complicated than a HERMS.

Me neither, but I currently use a plastic flow meter (non food rated) that automatically shuts off my RIMS tube if it measures too little flow. This has saved me more than once when I turned around and had a stuck mash. At least this way I could get that piece plastic out of my wort's line and not worry about burning... or non food rated plastic...

I already have everything I need sitting around... now that I have this stuck in my head I'll run some temperature control tests sometime and see if I can't get some hard data on ramping speeds.

I use the same FM. I have researched some non-contact SS FM's, but just not implemented yet. This thing has taken a great amount of abuse with no issues, and considering it is a $15 part - I would be happy replacing it every now and then anyway.
 
You can ramp faster than HERMS with this method, but not faster than normal RIMS. With RIMS, all of the power generated goes into the mash. With an intermediate heat exchanger, you will not be able to transfer all of the heat. As the CFC's transfer inefficiency increases, you would approach a limit of the boiling temperature of the RIMS water, and then you couldn't add any more heat. That said, the copper CFC probably has pretty good transfer efficiency.

And that that said, it will ramp fast, and fast is probably fast enough. No doubt it is a better solution than HERMS, which personally I think is a foolish and outdated technique altogether. But what do you gain besides complexity? Why not just use high power RIMS? Ensure the recirculation rate supports the heat you are adding. With that flowmeter and modern controls, you could easily set a heat amount commensurate with the flow. Or let the PID do the work (with proper tuning). As I said, I mash out with 5500W RIMS heat at full power - and raise 7+ gallons of mass in under 10 minutes from ~152 to 170 degrees.
BTU
As unpopular as this sentiment is... I would also say that copper is a good route to go. I am trying to eliminate all copper because I believe Cu toxicity is a real possibility (elevated temperatures, lower pH, leftover corrosion), and I want to move toward LODO, which we confidently believe is a no-no. I currently use a Cu CFC, but its going away soon.

The heat transfer between a surface and the wort is delta Temp x area, where deltaT = Thlt - Twort.

Assuming that you are going to limit the max temp of the surface so that the wort isn't going to scorch, the HX with the most area can provide the most heat. That would clearly be the CFC.

Then there is the issue of stored energy. A 10 gallon HLT with 180F water heating 145F Wort has 10 x 8.33 lbs/gallon x (180F-145F) = 2915 BTUs before the element is even turned on.

For mash out, boost the HLT temp to ~200F. It will pull down to sparge temp (175F) raising the mash from 150F to 175F, depending on the volumes. This is all without even turning the element on and the heat rate is solely dependent on the CFC HX area, with zero chance of scorching irregardless of the flow rate.

There is a lot to be said for using a CFC as an HX in a RIMS system. If I was building a 3 vessel system, I'd be using a CFC HX for RIMS. I was going to do it with my steam system.

If I was going to do an electric RIMS system, I'd set up a tiny water vessel with the coil in it like Paul Wicksteed did.
 
As unpopular as this sentiment is... I would also say that copper is a good route to go. I am trying to eliminate all copper because I believe Cu toxicity is a real possibility (elevated temperatures, lower pH, leftover corrosion), and I want to move toward LODO, which we confidently believe is a no-no. I currently use a Cu CFC, but its going away soon.

Do you have any reading material on the copper toxicity?

I googled up and skimmed through your recent thread where you asked the question on copper toxicity. It's an interesting question and was dissapointed the thread was closed... So I'll ask you here:
1) So if I wanted to test for this I just send off a sample to ward labs to look at copper alone? What about these verdigris compounds.
2) Since I obviously can't see inside the new cfc any advice on an initial cleaning procedure? (Can't forget that I'm unable to physically scrub the inside walls of the convoluted tube)
 
I googled up and skimmed through your recent thread where you asked the question on copper toxicity. It's an interesting question and was dissapointed the thread was closed... So I'll ask you here:
1) So if I wanted to test for this I just send off a sample to ward labs to look at copper alone? What about these verdigris compounds.
2) Since I obviously can't see inside the new cfc any advice on an initial cleaning procedure? (Can't forget that I'm unable to physically scrub the inside walls of the convoluted tube)

Do they scrub the inside of the copper tubing used in home plumbing ? Nope. Copper is a food safe, potable water safe, heated potable water safe material.
 
Here are the videos for Paul's brewery and RIMS.

[ame]https://www.youtube.com/watch?v=42LIz4KQQYM[/ame]

[ame]https://www.youtube.com/watch?v=RIJascCLwHo[/ame]

[ame]https://www.youtube.com/watch?v=djQGfrJKwgw[/ame]

Discussion of the HX starts at 5:40 of this video. Mention of a larger article on it too.

[ame]https://www.youtube.com/watch?v=EZBBmPdL9xI[/ame]

Lots of good ideas here.
 
Good numeric fodder there brewman. If you believe a RIMS + CFC is better than RIMs alone, go for it - it's your brewery.

Regarding Cu toxicity, it may not be a factor in our application. The reality is there is scientific evidence showing it is toxic at certain levels in the bloodstream (like any compound, really). Whether or not those get approached in our applications has yet to be demonstrated. In the thread where I posed it, I only asked for evidence and did not make a claim one way or another, yet everyone got huffed because the concept challenged their steadfast beliefs. My personal belief is to minimize its use. I also want to integrate LODO in the future, so this plays a factor as well.

If you really wanted to be sure, a test of a sample pre and post fermentation would be a good idea. PBW can effectively remove deposits, oxidation, etc. I don't know if that's a good thing or not, but my personal assumption is the oxidized layer is more stable, so removing it exposes Cu again.

By the way, just because something was done a certain way for a long time doesn't mean it was a best practice. It just means it was done a certain way for a long time.
 
Good numeric fodder there brewman. If you believe a RIMS + CFC is better than RIMs alone, go for it - it's your brewery.

My brewstand is single vessel, like a Grainfather on steroids, with a 5 Kw induction heat system. Should I have issues with direct heating the mash, I have purchased all the parts to build an HX like Paul did and I'll use it for mash heating.

By the way, just because something was done a certain way for a long time doesn't mean it was a best practice. It just means it was done a certain way for a long time.

Copper pipe has been used in potable water systems and various cooking vessels forever. If Cu toxicity was an issue, there would be a wealth of medical evidence proving it. It is called the test of time.
 
My RIMS tube was having problems last weekend during a brew. I needed a quick solution to bring the temp up to 150 for mash and set up my copper cfc as a herms, using my hlt as heat source. After using it I don't see why people put extra coils in their hlts. I get the same functionality as the herms in the coil with no added expense because I bought the cfc to chill the wort. I see no reason your set up wouldn't work you just need to find the sweet spots for temps. Like when my garage is 50 i need to be 10 degrees over on my hlt to hit my mash temps. All your doing is making a smaller hot water reservoir to hold temps as long as your element can over power the temp differentials you want to do It should work like a champ.
 
My RIMS tube was having problems last weekend during a brew. I needed a quick solution to bring the temp up to 150 for mash and set up my copper cfc as a herms, using my hlt as heat source. After using it I don't see why people put extra coils in their hlts. I get the same functionality as the herms in the coil with no added expense because I bought the cfc to chill the wort. I see no reason your set up wouldn't work you just need to find the sweet spots for temps. Like when my garage is 50 i need to be 10 degrees over on my hlt to hit my mash temps. All your doing is making a smaller hot water reservoir to hold temps as long as your element can over power the temp differentials you want to do It should work like a champ.

The easiest way to control mash temp with the CFC RIM system is to tie the mash PID output to the HLT pump and run the HLT itself at a constant temp via its own PID.

Thus the mash is set to circulate continuously or as needed, through the wort side of the CFC. When the mash temp drops the PID output will kick on the HLT pump and circulate hot HLT water through the water side of the CFC, thus heating the wort, thus heating the mash. The HLT has its own PID controller that keeps the HLT water at a constant temperature. No human intervention needed with either vessel.

FWIW, the max practical HLT temp for mash heating is 210F, depending on the elevation. Paul's system kept the water under pressure and would allow operation at temperatures well above an atmospheric boil.
 
Does any one use there CFC double duty to maintain mash temps as well as cool?

I'm in the middle of rebuilding my little system. Here is the progression of what I've done so far and what I'm thinking:
  • I had been using a 1,375 watt RIMS tube to control my mash
  • I just picked up one of these fancy all copper ZChiller's with the convoluted inner tube (counter flow chiller) because I was tired of my DIY immersion chiller
  • I have a handful of these cheap DC tan pumps sitting around.. so extra pumps
  • I've already just installed 240v service in the garage because I'm working on an electric kettle

So, here is what I'm thinking: Why not use the CFC as a HERMS as well as a chiller? I'm thinking of reusing the RIMS tube as the heat source for the CFC. The RIMS has a 5500 watt element in it so I'd rewire it for 240v. Id recirculate a small amount of heating water for the RIMS tube in my old dusty kettle from extract days.

I can't help but think I'm just over complicating things but I also think there could be some advantages here. I'm wondering if with the 240v RIMS tube as the heat source through the CFC if I could ramp temps quicker than with either a standard HERMS/HLT or with my 120v RIMS directly inline with the wort? I think back to brewhardware bobby's youtube video showing him using a 5500 watt RIMS tube for on demand sparge water.

I'll also have the benefit of knowing that I wont scorch my wort, not that I have ever scorched my wort with my 120v RIMS. (but there was always the possibility) Given that I haven't had scorching issues this only matters if my first assumption that ramping will be quicker turns out to be true.

Also, my RIMS tube is an old school DIY screwed together out of a bunch of SS pipe fittings, if I'm only ever running water through it now I don't have to worry about taking it apart and cleaning it any more.

Thoughts?

For reference:
CFC: https://www.zchillers.com/product/large-zchiller/
Bobby's on demand sparge water: https://www.youtube.com/watch?v=0AGUOCeM-WU&t=160s
OI have no reason to believe it wouldnt work but I Guess I just fail to see the advantage here over just using the rims to heat the mash directly? what your proposing would be a more complicated less effective system right? is there something about your rims configuration that doesnt perform well?
 
OI have no reason to believe it wouldnt work but I Guess I just fail to see the advantage here over just using the rims to heat the mash directly? what your proposing would be a more complicated less effective system right?
I should mention because I don't think I had previously that I am looking at doing 1v biab.

My first response: common guys, this isn't complicated. It's just a little bit different approach than we're used to. Look at post #8, it's super simple. It's certainly no more complicated than HERMS. I have one wort loop, and one heat exchange loop, no hose changes for the whole brew. I have no need to disassemble my pita rims tube for cleaning either.

Less effective? That's the real question that I want to explore. Can I get quicker (scorchless) heating out of a 5500 ultra low volume HERMS vs a 1375 watt rims? Remember I'm talking about using equipment I already have, not CFC herms vs buying a more powerful rims element. That said, does anyone use a 5500 watt rims? If that's something that can be done easily and safely for the extract then hell yeah that's the way to go!

I understand that direct heating wort is more efficient, but what I'm talking about is a 'maximally efficient', fast reacting HERMS system at much higher wattage vs the standard rims.

Also, Alton Brown would be proud if I could turn my unitasking CFC into a bonafide multitasker.

is there something about your rims configuration that doesnt perform well?
Nah, It's fine. But that's not so much the point as much as I *might* could reconfigure my system w/ equipment I already have to make things a little smoother on brew day. Separate heating and cooling systems would mean either extra hose changes or more valve purchases.

On second thought, there is an issue: stuck sparges! I mentioned earlier that they have happened to me on occasion, this configuration eliminates the risk of either scorching wort in a rims tube or running the element dry. I suppose these are just HERMS vs RIMS pros and cons that we all already know. And I'm in no way trying to spark some kind of herms v rims debate either.
 
...I mash out with 5500W RIMS heat at full power - and raise 7+ gallons of mass in under 10 minutes from ~152 to 170 degrees...

...That said, does anyone use a 5500 watt rims? If that's something that can be done easily and safely for the extract then hell yeah that's the way to go!...

[insert foot in mouth]

What's your flow rate at mashout, BrunDog?
 
I see your points. I suppose I could say your setup could likely be made to avoid the things you dont like in other ways too but it would require different hardware so that would justify your approach.

I do not have any hoses or fittings to move or a rims that required disassembly to keep clean... .. I clean it the same way you would a CFC... also as you might remember theres a lot of ways to avoid the stuck sparge which if your experiencing them can be argued as a flaw in your system or process as well right? I havent had any stuck sparges in a very long time but I have a flow switch which prevents the possibility of any accidents even if my super ULWD element rims flow did stop... It just seemed odd because you would be using a rims but to basically control a herms coil... and I dont see how that works for chilling too without redirecting or changing hoses?
 
also as you might remember theres a lot of ways to avoid the stuck sparge which if your experiencing them can be argued as a flaw in your system or process as well right?
Indeed.
I havent had any stuck sparges in a very long time but I have a flow switch which prevents the possibility of any accidents even if my super ULWD element rims flow did stop...
I have a flow meter that protects me from this risk as well... But it is complication and potential point of failure that I could eliminate from my system.

It just seemed odd because you would be using a rims but to basically control a herms coil... and I dont see how that works for chilling too without redirecting or changing hoses?
I've got a 3 way valve, I'd put my coolant water on one input and the "heatant" on the other. There is one hose change here, I'd pull the return hose from the heating reservoir (mini hlt) and drop it in a waste bucket.

MdtVWiO.png
 
*sigh* For some reason I'm compelled to keep defending the idea... Maybe I'm just trying to squeeze more utility out of a $150 chunk of copper. Before we keep going down this path I can say right now that I'll probably end up scrapping all of it and simply doing direct fire ebiab when ever I eventually get a proper false bottom for my new kettle. ( This thread was started a day before I made the decision on a biab setup )
 
I totally get understand when you find yourself married to an idea and keep defending it - I do that all the time. But since you posted publicly requesting comments, you are getting them! I noted above, and AD followed suit that we don't see the benefit of this over standard RIMS, because we both use one successfully. It comes down to this: is my extra hardware going to be the CFC as RIMS/HERMS hybrid, or a flow sensor in my normal RIMS? To us, it is easily the latter. The combination of a flow switch or meter with a PID makes this kind-of a non-issue. I have never scorched wort in fact.

I would say that if you use 5500W power in a closed loop, it will likely boil the water so fast you run the risk of an overpressure situation and will need to manage it's temperature very closely. That much power will bring the small volume of water in your loop from 155 degrees to 212 in a heartbeat! That may be the purpose of your cooler-grant in the picture above. But again that is extra hardware.

In terms of efficacy, RIMS will be the most effective because you are not using an intermediate heat exchanger. This is not refutable. I totally see the benefit if you wanted to use HERMS and didn't want to bother heating all that water in your HLT to do it (hence why I personally eliminated the pesky HLT altogether as AD noted). But since you are using RIMS, why not just use RIMS?

As mentioned, I use the full power for mashout and direct heating of sparge water, and it works very well. The sparge side needs extra hardware and controls - no doubt. Tangent: I don't use PID btw... because the flow is controlled, I use duty cycle at around 65% to get water heated from ~75 to 170 degrees at ~1 qt/min. My control system measures the flow rate on average, and if the flow is >1.15 qt/min, is slightly closes the proportional valve, vice versa if the flow is < 1 qt/min.

With respect to flow rates and stuck sparges... yes this is an issue. I have learned to tighten up my flow initially, so I probably start around 6 qt/min immediately following dough-in, and I am almost double that at mashout. That intial slow flowrate makes my PID chase a bit, but once in the middle at around 10 qt/min its money. At the end rate, it allows for the 5500W to be on 100% during mashout, so its lot of heat going in, which is why I can mashout so fast. I would say my wort leaving the RIMS tube is ~190 degrees at that rate/power. Of course, many will argue mashout is unnecessary, but I do it. The wort needs to be heated for the boil anyway, so 5500W there or 5500W in the BK is an even trade.

Hey, at the end of the day there are lots of ways to address problems and solutions. You need to do what you like and try some things that you think may work for you. I change my design constantly. I have so many spare parts from stuff I tried it fills a couple of boxes. This is part of the fun. So whats the worse thing that happens if you try it? You said you already have the pumps and CFC, so plumb it up and give it a whirl.

On my way out I will drop this little bomb... one thing I am testing is an inverted mash (flow from bottom to top). It is intended to accommodate LODO, will allow for grain underletting, and as a side benefit, will avoid stuck mashes forever.
 
You're correct about the cooler-grant in the pic, no closed loops. I'm not trying to make pipe bombs over here.

I suppose the stuck sparge is another discussion. I think that's an issue with my old cooler mlt's manifold. Hopefully that'll be remedied in the biab setup. My flow rate "schedule" actually looks an awful lot like yours.

Yes! Inverted mash, I've thought about that too. My hangup on that was how do you keep your pump primed with out making a mess? I'm eager to see what you come up with. I've had some ideas but nothing ... elegant.
 
I am using motorized ball valves so no hose switching, but it could certainly be done with manual valves., For LODO I would boil water in the BK then cool it on the fly into the RIMS, heating it again slightly to be at proper "strike" temp. The liquid comes in through a ring at the bottom of the grain, underletting it. Then once filled to proper amount, start recirculating.
 
Not sure I follow entirely.

Then once filled to proper amount, start recirculating.

Though from the top of the grain bed, right? That's the tricky part. Is the ring you mentioned connected to your drain valve? What if the ring were adjustable and separate from the drain, you put the ring on the bottom of the mash tun to fill/underlet and when ready to recirculate you bring the same ring back to the top and reverse the flow? ...I imagine getting into messy hose swaps again though.
 
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