Hybrid RIMS & HERMS.

[Acidjazz54]

I wanted to get everyone's opinion on my new brew rig design.

I am looking at doing a hybrid HERMS and RIMS setup that will give no risk of scorching the wort.

The HLT will have a ball valve at the bottom that leads to a pump. From the pump the hot water goes through a "RIMS" type heater. This allows small amounts of water to be heated at a time rather than heating the entire 10-15 gallons in the keggle. The tree hugger in me thinks that this should be much more efficient than simply placing a heating element in the bottom of the HLT. This is the "RIMS" part.

For the HERMS I would have a typical HERMS that cycles the wort through the heat exchanger in the HLT.

I guess there isn't much about this setup that is too exciting but I wanted to see what people thought of the efficiency of the water heating. Let me know your thoughts and any suggestions. Cheers!

 

[SSRider]

That is sort of what I am building now. Instead of using my HLT to heat the mash, I am building a heat exchanger in a 1/6 barrel keg. Instead of having to heat the entire HLT to raise the temps, I will only have to do a small volume. It will probably be around 2 gallons. that actually get used. Im going to insulate it and run copper coil through it for the mash to flow through. I should be able to achieve step increases much faster than with the HLT. The heat exchanger will have its own ranco controller for doing the temp increases. A corny could be used instead, but I am getting the 6th barrel for free so thats what I am using. I have also seen it done with a small 1 gallon cooler as well.

 

[The Pol]

I dont get it...

Instead of putting a heating element in the HLT, you are putting a heating element in a RIMS type cylinder and pumping the HLT water through it, and back into the HLT? You said that your HERMS coil is still going to be IN the HLT?

I guess I am confused... you said you are pumping HOT water from the HLT through a "RIMS type heater". How is the HLT water getting heated in the first place? Also, after the HLT water runs through the "RIMS" heater, where does it go? Back to the HLT? How is this faster than having an element in the HLT?

Maybe I am missing something, but if you are running water from the HLT through a heater, then back to the HLT, you are losing heat during the pumping and transfer, so it would take longer to heat your HLT water that you are using for your HERMS. You are exposing your HLT water to a lot of surface area in the hoses and pump, thus losing heat to the ambient air around it.

Bottom line is, if you are running a HERMS with a coil in your HLT... the fastest way to heat the water in the HLT is with an element placed directly in the HLT.

If you want to heat the HEX water faster you need a completely separate heat exchanger, in a small vessel, complete with a coil (say a 3 gallon cooler) then that would be faster than the HLT, yes. But then you would not be pumping any water, just wort through the heat exchanger coil in the small vessel. You would be changing the temp of say 2 gallons of water instead of 6 or 7. But if you have the coil in the HLT, an element in the HLT is the most efficient way to heat the water in ther for the HEX.

 

[SSRider]

My heat exchanger will be completely separate.

I think he was thinking that he could pull water from the HLT and heat it on the way to the mash. But the only way that would work is if there was a coil in the mash, not in the HLT

 

[The Pol]

My heat exchanger will be completely separate.

I think he was thinking that he could pull water from the HLT and heat it on the way to the mash. But the only way that would work is if there was a coil in the mash, not in the HLT

Yeah, I totally get what you are doing... thought if that too when I built my HERMS. I can use my HLT for step mashes, so I didnt do the separate vessel thing. I heat 9.5 gallons in my HLT to say 140F... hot enough to strike at 130F, using 10F to preheat the MLT and protien rest at 122F. By the time that rest is complete (20 min) my HLT volume is at 157F so that I can start my recirc and heat my mash to 153F for the alpha rest.

The OP, I dont understand at all. He stated that he will still have a HERMS coil in the HLT, sooooo, wouldnt you want to heat the HLT, since that is where the coil is getting its heat?

The only faster way to heat a HERMS HEX is to use a smaller, separate vessel like you are.

Using a coil in the MLT makes no sense either, since you would then need to have a mash mixer so that the mash would heat evenly and not get hot next tot he coil and cold further from it.

I am very confused.

 

[SSRider]

There is a guy in my local homebrew club who is going to put a coil in his mash to raise temps, which is backwards from the way most people do. But I guess it would work. If I understand what the op is wanting doing, the coil in the HLT is unnecessary. You would just pump the HLT through the rims style heater, then into the mash, through the coil, then back to the HLT. It would slowly raise the temp of the HLT also. Im not sure how efficient it would be though. I guess the water coming out of the rims heater would be relatively hotter and would raise the mash temp, but you would still need to measure the temp of the mash and control the heater. I think it could work, and I dont see it scorching the mash, but for me it makes more sense to do an external heat exchanger. There are benefits of the external heat exchanger, such as setting the grain bed and recirculating the mash so when its time to sparge, the wort is already clear, but I dont see any added benefit to the coil in the mash setup and like you said, the mash would need to be stirred. Although I have not thought that type of system out either.

 

[The Pol]

Yeah, with a coil in the MLT, youd not set up a nice grain bed, youd need a mash stirrer... it would be a mess.

Dunno, we will have to have the OP enlighten us!

 

[Seabee John]

+ one for the "too much of a mess" category. I have a gas / electric style RiMS system. Because I'm using an element on 110v, it's a bit of a stretch to heat 10 gallons of mash from a 122 deg protein rest to a 154 Sacc rest in a short enough time. So, I installed a burner under my MLT.

I'm not worried about scorching the wort, because of three factors:

1. the rate of flow of the pump lessens the exposure time of the wort to any heating surface.
2. because I'm heating with a RiMS and backing that up with direct fire, my burner barely needs to be on to provide enough extra heat to achieve my temps in the right amount of time.
3. I'm using an ultra low density 4500w element which has the largest possible surface area for heating which means less chance of scorching.

Now, in defense of those brewers who have been brewing much longer than I.

-what's so wrong with a little scorched wort??? It adds both color and flavor and is an integral part of a lot of recipes. I started out on a herms and I love my RiMS so much more.

 

[caskconditioned]

That is sort of what I am building now. Instead of using my HLT to heat the mash, I am building a heat exchanger in a 1/6 barrel keg. Instead of having to heat the entire HLT to raise the temps, I will only have to do a small volume. It will probably be around 2 gallons. that actually get used. Im going to insulate it and run copper coil through it for the mash to flow through. I should be able to achieve step increases much faster than with the HLT. The heat exchanger will have its own ranco controller for doing the temp increases. A corny could be used instead, but I am getting the 6th barrel for free so thats what I am using. I have also seen it done with a small 1 gallon cooler as well.

This is what I do (I think I've mentioned it to you before). But I'm using a bucket heater in my HERMS chamber (1500w). It was the simple solution at the time and does a great job of maintaining mash temps and doing small adjustments. I think I get about a 1 degree change per 3 minutes. However, in my case, the heater is not powerful enough to do serious step mashes. I will be converting my brewery to electric next year (thanks for all the info Pol) and at that time will be replacing the bucket heater with a more powerful heating element so that I can do step mashes. I am still a huge fan of a separate HERMS chamber. And if I ONLY wanted to maintain mash temps - then my current solution would suffice. And in truth, I rarely do step mashes. But the tweaker in me always wants to improve things.

 

[Acidjazz54]

Pol,

You are correct, I was planning on using the heating chamber to simply heat the water in the HLT. My thought was that the smaller volume of liquid (the heat chamber) would heat the HLT faster than trying to heat the entire HLT at once because of the thermal mass of the water in the tank. I didn't however take into account the heat loss that I would have back and forth from the heating chamber.

Seabee,

I didn't think completely about doing step mashes. My ultimate plan is to automate a lot of this much like the Deep Six Brewing rig. That being said I think this type of setup would make it harder to increase the temp of the mash. Where did you pick up the ultra low density element? I remember seeing a link on one thread but have since lost it.

SS,

I like the idea of using a smaller vessel to put the heat exchanger in but I think ultimately it would be easier to cycle the heating element on and off rather than cycling the pump on and off.

Thanks guys for your suggestions it's much appreciated. I'll keep searching the threads to see what others are doing.

 

[The Pol]

OK, yeah if you are simply trying to heat the HLT water, the fastest way to do it is with an element immersed in the HLT. There is a lot of thermal mass there yes, but that thermal mass is still there, even if you are heating small ammounts of water at a time and adding them back to the HLT, you gain nothing. You are heating the same ammount of water, with the same number of watts of power... you are just making it more inefficient by pumping it and transferring it.

Id do a straight up RIMS (ULDW element) or a HERMS with a large element (6500W). No need to worry about watt density in the HERMS, because it is just heating water.

 

[Acidjazz54]

I want to do an entirely electric system. Should I use an ULWD element for the boil kettle also? Also, what wattage would you suggest to bring the BK to a boil?

 

[The Pol]

Anything that is coming into contact with the wort should be ULWD... if you are brewing 5 gallon batches, you can use a 5500W RIPP element in the BK. If you are doing 10 gallon batches, you can go ahead with (2) 4500W or (2) 5500W elements (for quicker boiling of large volumes). You could get away with ONE 5500W ULDW element, but it would take a while to get it boiling in the BK.

In a RIMS heater, you could easily get away with a 4500W or 5500W standard element, but run it on 120VAC instead of 240VAC. This will yield less wattage, BUT it will make the element ULWD (less than 50W per square inch).

The reason being that you dont need 4500W or so to run a small RIMS heater, and you cannot find ULWD elements in the 1500W-2000W range too easily.

 

[Windsors]

I was using the a conventional HERMS coil in the HLT. In my older HERMS system, when I heated up the HLT water to keep the mash temps where they needed to be, I was heating up the entire HLT to temps that were higher than what I wanted for sparging, so I had to cool the HLT water before sparging and it was pretty inefficient. I have always liked the HERMS system since I never wanted to deal with the potential to scorch the wort. I was also using a pump to recirculate the HLT water to keep it at a consistant temp.

I found a 2.5 gallon SS heat exchanger with a 25 ft SS coil on the inside of it. So I added a heating element to the bottom that sticks up vertically. I recirculate the HLT through the cylinder and the mash through the coil. I turn the element on and off with a PID connected to a RTD measuring the mash temp.

It's a combo RIMS / Herms unit. I was already pumping the HLT water to recirculate it, so now the pump serves another purpose. Other than water testing the system, I have not finished with the rest of my changes yet to brew after these con the new RIMS / HERMS.

I think this will be more efficient since I am only heating a small amount of water to transfer heat to the wort instead of heating up the entire HLT water.

Here are some pics of the RIMS / HERMS combo and one of the system.

Any thoughts ?

 

[Windsors]

More photos...

2nd from the bottom is the front shot and the last is the back shot. Low voltage control panel did not make the shot.

 

[audger]

Pol,

You are correct, I was planning on using the heating chamber to simply heat the water in the HLT. My thought was that the smaller volume of liquid (the heat chamber) would heat the HLT faster than trying to heat the entire HLT at once because of the thermal mass of the water in the tank. I didn't however take into account the heat loss that I would have back and forth from the heating chamber.

even if you ignore the radiation losses from pumping it around a longer loop, heat is heat. it takes the same amount to heat the HLT regardless of weather you heat it directly with an element in the HLT, or remotely by pumping hot water into it. its all the same amount of energy.

using a HERMS to heat the HLT will be less efficient not because of the extra radiation losses (which are relatively small) but because of the disconnect between the heating element and the water you want to heat (now you have another water loop between them with a HERMS). every time you chain a heat exchanger, you loose efficiency. the more number of exchanges there are, the exponentially greater your losses will be, because the losses compound at each step.

also, now instead of heating 10 gallons of water in the HLT, you have to heat those same 10 gallons plus the remote HERMS pot.

 

[Windsors]

I wasn't clear with what I am doing.

I still have an element in the HLT to heat that water when activated.

The 2.5 gal HEX cylinder has its own element is to heat the water which heats the wort which flows through the coil in the HEX 2.5 gal. cylinder. The wort then flows back to the mash tun and the water flows into the HLT.

While the wort is being recirculated through the 2.5 gal HEX, the element will fire when called for by the PID controlled by a RTD temp probe in the wort stream. The water is being recirculated through the 2.5 gal HEX and through the HLT. While the wort is being kept at temp, the HLT element won't have to fire much. Then when I ramp up temps to sparge, the HLT element will fire from a PID controlled by a temp probe in the HLT.

To me this works well in my head. Haven't tested it with a brew yet.

 

[thelorax121]

Windsor, where did you find that HEX?

 

[Windsors]

It was an ebay find a couple of months ago. I was searching for heat exchangers. They didn't have very good photos and it was pretty dirty, but they took my offer of $120 shipped, so I took a chance. I think it will work out.