Understanding HERMS Systems

So I've been brewing BIAB for a while now but am starting to get the "itch" to spend some more money and do more in depth all grain brewing. I've been looking into the details of single tier 3 vessel brewing with HERMS system. It looks very convenient to have everything set up already on a stand ready to go, and not have to lug around kettles and stuff.

Let me see if I've got this right for the basic system as far as how it works:

1. You heat up strike water in the HLT on the far left to your strike temperature and transfer it to the MLT. Is this right or do you heat up strike water in the MLT?
2. Dough in to your MLT and re-circulate the mash through the HERMS coil in your HLT which is set at the temperature you need to hold the mash steady?
3. At what point do you heat the HLT water to your sparge temperature? Will this not effect the temperature of the mash since you are using a HERMS coil in this water, or do you start heating sparge water after the 60 minute mash is complete?
4. Start first runnings/sparging with 170F water from HLT.

Since you asked about heating the strike in the MLT, I assume you have (or are considering) a metal MLT. I do, and I also Batch sparge, so here is what I do...
Heat the strike volume in the MLT to the temp. This ensures the MLT is completely up to temp.
Set the HLT to the strike temp and circulate through the hex and make sure everything is a stable temp.
Turn off the pump and dough-in. If the temp is high, continue to stir until the temp drops. If the temp is really high, add some cold water and continue stirring.
Once it is completely stirred (no dough balls) and the correct temp, cover and let set for at about 10 minutes to set the bed.
Set the HLT to the correct temp. I usually go 1.5 deg F higher than mash temp, and add a little cold water to get it down to my desired temp, and then start the re-circulation through the HEX. Adjust the flow so that you have good flow, but not so fast that it sticks.
After conversion is complete, drain to the BK and measure the volume.
Calculate how much sparge running is needed to hit your pre-boil volume.
Add that amount from your HLT to the MLT and stir for several minutes.
I usually wait for 10 minutes to set the bed after stirring, but many just immediately drain.
You should end up with your exact pre-boil volume.
In my opinion, there is no reason to heat the sparge beyond what you already have on hand as no mash-out is needed for this method of sparging.

My system is a Kal Style HERMS setup, so your exact mileage may vary.

1. I fill my HLT and set it to heat to my mash temp. At this point the MLT is empty.
2. I transfer my strike water into my MLT and dough in. I start circulating the mash through the coil and keep the HLT set to my mash temp.
3. HLT and MLT maintain mash temp for the entire mash.
4. I set the HLT to Mash out/Sparge temp.
5. The HLT reaches that temp and is shortly followed by the MLT.
6. I start Fly Sparging.

Hope that makes sense. Kal has a step by step here.

arnobg said:

1. You heat up strike water in the HLT on the far left to your strike temperature and transfer it to the MLT. Is this right or do you heat up strike water in the MLT?

It is up to you; either way works. The advantage of directly heating the MT is that the lower volume of water will reach strike temperture more quickly. The disadvantage is that you can't use a cooler. In my system, I heat the MLT to strike temp while heating the HLT to mash temp. That is quicker than heating the HLT to strike temp plus I don't have to cool the HLT to mash temp for recirculation.


2. Dough in to your MLT and re-circulate the mash through the HERMS coil in your HLT which is set at the temperature you need to hold the mash steady?

Yup.

3. At what point do you heat the HLT water to your sparge temperature? Will this not effect the temperature of the mash since you are using a HERMS coil in this water, or do you start heating sparge water after the 60 minute mash is complete?

You can stop recirculation while heating the MLT to sparge temp; this will let the HLT reach sparge temp more quickly. Or you can just start the ramp up to sparge temp after the mash rest is complete and let the mash ride along. That is what I do. It depends on how much delta-T you can get in your HLT.

4. Start first runnings/sparging with 170F water from HLT.

Click to expand...

Yup.

arnobg said:

1. You heat up strike water in the HLT on the far left to your strike temperature and transfer it to the MLT. Is this right or do you heat up strike water in the MLT?

Click to expand...

Not exactly, I have a Electric Brewery setup I built myself from kegs. I actually fill my HLT to the top and fill the MLT to the proper strike volume and recirculate the MLT water through the HLT to bring them both up to temp at the same time. I use Beersmith to calculate the proper temp. I find this the ideal process since both pumps are primed and everything is up to mash temp except the grain.

arnobg said:

2. Dough in to your MLT and re-circulate the mash through the HERMS coil in your HLT which is set at the temperature you need to hold the mash steady?

Click to expand...

Yes, that is the beauty of HERMS, the wort is circulated through the HLT which in my system is set 1-2 degrees above the mash temp to accommodate for heat loss.

arnobg said:

3. At what point do you heat the HLT water to your sparge temperature? Will this not effect the temperature of the mash since you are using a HERMS coil in this water, or do you start heating sparge water after the 60 minute mash is complete?

Click to expand...

After my hour mash, I start ramping the HLT to 172 degrees. It takes around 17 minutes for my MLT to reach 168 degrees with a 10 gallon batch. I hold 168 degrees for 10 minutes then fly sparge over the period of an hour.

Chris

Good info thanks. I've noticed a lot of people start heating up their boil kettle when getting close to the end of their sparge. Does this not make it inaccurate measuring the boil volume as it heats up and expands?

I would be most interested in fly sparging with the setup. In this case I will only be having "first runnings" correct?

jrcrilly said:

Yup.

Click to expand...

What is delta-T?

arnobg said:

Good info thanks. I've noticed a lot of people start heating up their boil kettle when getting close to the end of their sparge. Does this not make it inaccurate measuring the boil volume as it heats up and expands?

I would be most interested in fly sparging with the setup. In this case I will only be having "first runnings" correct?



What is delta-T?

Click to expand...

Yes, you'll have rich early runnings and lean late runnings, but it will be a continuous process. I like fly sparging and use it when on the "big rig" but can't provide any compelling argument in favor of it. It is just a personal preference

Delta-T is change in temperature per unit time. It determines how long it will take to reach mash, strike, sparge, mashout (those last three are usually the same or at least similar) , and boil temps. If your system delivers much less than 2 degrees F (or 1 degree C) per minute stepped mashes and/or mashout may be problematic and might have to be avoided.

I have a three kettle system powered by propane and a 1500 element in the hlt. I use propane and element together to get to proper HLT temp. Once the proper HLT temp is reached, the propane is not used. I use propane to reach MLT temps.

1. Heat 9 gallons water in HLT to proper temp to maintain mash temps. Usually +4 degrees. Pump on to recirculate HLT water.
2. Heat required water in MLT to strike temp. Pump recirculates MLT liqueur through coil in HLT . This may raise the HLT some but has not caused a problem.
3. Mash in. MLT pump is off. Then turn pump on. Mash recirculates through HLT in the coil and back into MLT to maintain temps.
4. After mash is complete, move tubing for fly sparging. Pumps wort into the brew kettle and sparge water through coil and then into MLT. This cleans the coil.
5. I do turn on the boil kettle burner on at 5 gallons to start heating the wort for the boil.

Here is a picture while sparging.

Do you typically only fill the HLT up to an amount to completely surround the HERMS coil, or are you filling it to a calculated amount with Beersmith that is known that you will be fly sparging with? Is there normally water left in the HLT when sparge is complete or are you draining the entire tank and you know you should then have your boil volume because of calculated losses on your systems? Hope that my question makes sense.

This has been helpful thanks for all of the explanations.

tdbc2011 said:

I have a three kettle system powered by propane and a 1500 element in the hlt. I use propane and element together to get to proper HLT temp. Once the proper HLT temp is reached, the propane is not used. I use propane to reach MLT temps.

1. Heat 9 gallons water in HLT to proper temp to maintain mash temps. Usually +4 degrees. Pump on to recirculate HLT water.
2. Heat required water in MLT to strike temp. Pump recirculates MLT liqueur through coil in HLT . This may raise the HLT some but has not caused a problem.
3. Mash in. MLT pump is off. Then turn pump on. Mash recirculates through HLT in the coil and back into MLT to maintain temps.
4. After mash is complete, move tubing for fly sparging. Pumps wort into the brew kettle and sparge water through coil and then into MLT. This cleans the coil.
5. I do turn on the boil kettle burner on at 5 gallons to start heating the wort for the boil.

Here is a picture while sparging.

Click to expand...

How do you accurately measure pre-boil while heating it up when your sparge is not complete? Or is my answer in my question above?

arnobg said:

Do you typically only fill the HLT up to an amount to completely surround the HERMS coil, or are you filling it to a calculated amount with Beersmith that is known that you will be fly sparging with? Is there normally water left in the HLT when sparge is complete or are you draining the entire tank and you know you should then have your boil volume because of calculated losses on your systems? Hope that my question makes sense.

This has been helpful thanks for all of the explanations.



How do you accurately measure pre-boil while heating it up when your sparge is not complete? Or is my answer in my question above?

Click to expand...

1. I fill the HLT to the top of the 10 gallon kettle which covers almost all of the coil. 9 gallons is always enough to get the preboil amount that I want.
2. There is always water left in the HLT. I do not use Beersmith, but I used to calculate the amount absorbed by the grain and then subtract that from the strike water amount and then calculate how much sparge water I need. Now I just fill the HLT kettle!
3. I brewed my 70th all grain beer two weekends so I know how much I need preboil to get enough to end with 5.5 gallons. I normally have 7 gallons preboil and 7.5 gallons on big beers. I boil from 60 min to 90 min.
4. I am sure my "hot" measurement is not exact, but it has been close enough.

When fermentation is done and I am ready to keg, I check the amount in the fermentor which is marked on the inside by 1/2 gallons. If I have 5.5 gallons or above I transfer to SS mini keg growlers and prime with sugar. I then keg the rest (5 gallons).

I hope this helps.

arnobg said:

How do you accurately measure pre-boil while heating it up when your sparge is not complete? Or is my answer in my question above?

Click to expand...

Here is a chart.

http://westank.com/wp-content/docs/sizing/expansion.pdf

Looks like a coefficient of about .024 from 70 degrees to 175.
7 gallons x 1.024 = 7.168 gallons.