Pre-heating a keggle mash tun

[Chefboubou]

Guys, I've search the forum without luck for this question. I've just converted to 100% electric and my mash tun is a converted keg. I used to preheat the mash water in the MT on a propane burner. However, I will now use an electric HT. I am therefore wondering what should be my water temperature before it's been transferred to the MT, considering the temp will drop. I made some calcs and for 5.5 gal of water, I would need in theory to overshoot 5F above stricking temp. But I think it's not enough.... Could your experience? Thanks!

 

[Natdavis777]

I too use keggles, and I heat up my water in the BK and transfer to the MLT around 175F. I will let it sit in there for ~10 min with my reflectix wrap already on to set my thermal mass to 0. Then after the 10min I will stir the water until I hit my dough in temps (usually after 10 min I only need to drop it a few degrees).

I transfer via a pump though which allows me to maintain that 175F from the BK to the MLT. If you are having to drain it via gravity from one vessel to the MLT or drain into buckets and then add the water to the MLT, I would suggest a slightly higher temp to ensure you still have hot enough strike water after the walls are heated

 

[Chefboubou]

Thanks Natdavis777, I transfer by gravity (for now) so that gives me an idea. I will shoot for ~180F and will add water after 10 min if needed to reach striking temp.

 

[Natdavis777]

Good deal. Id say 180F should get you where you want to be

 

[CanAm]

This is quite timely for me too Natdavis777. I just got a keggle MLT. Thanks for the starting temp, but (and I know this is a basic question) how do you figure your dough-in temp? I use beersmith and they only give strike temp.

And I've found in the past with my cooler MLT the beersmith recommended strike temp was low. Their default for Stainless keg strike temp is 159 to get to 148 mash, which looks a lot lower than your actual working numbers.

Thanks!

 

[Natdavis777]

This is quite timely for me too Natdavis777. I just got a keggle MLT. Thanks for the starting temp, but (and I know this is a basic question) how do you figure your dough-in temp? I use beersmith and they only give strike temp.

And I've found in the past with my cooler MLT the beersmith recommended strike temp was low. Their default for Stainless keg strike temp is 159 to get to 148 mash, which looks a lot lower than your actual working numbers.

Thanks!

My dough in temp has remained the same for my first setup (cooler MLT) and my present keggle system. After pre-heating, I know I want to dough in around 164 for a rest temp of 152F (given that the grains are ~70F). I have around, if not more, than 100 brews so its something I have tweaked over time. So, in a nutshell, and given the constants (MLT thermal mass = 0, grain is @ 70F) I can anticipate a 12F drop. So, if I want a rest temp of 156, I need to dough in @ 166F.

One thing I would suggest is err on the warmer side. It is easier to stir your mash down from 156F to 152F than it is to bring the temp up the opposite way (given that you are not using HERMS, RIMS, direct fire)

 

[CanAm]

That's gold Natdavis777! Pure gold! I'm looking forward to using your numbers. Thank-you for sharing your experience.

 

[CanAm]

Forgot to ask - what's your preferred sparge temp Natdavis777? I imagine you fly sparge since you mentioned a pump...

 

[Natdavis777]

I do flysparge. I typically flysparge with 180F water. You dont have to worry about tannins with 180F sparge water because the actual mash never reaches 180F. It levels out around 165F...

 

[CanAm]

That's good to know. I may need to name my next brew "Copy Cat Saison" lol!

On the SABCO brew magic video it shows fly sparging and I gather the rate is about 1 quart/min or 1 gallon/5 min? Is that what you do?

And just to be clear (since I've only batch sparged before) once you've finished your mash, you drain the wert out at the rate you add the 180F water. Continue adding sparge water until the volume of wert from the mash plus the total volume of sparge water added will get you to your target boil volume, then turn off the sparge water and continue to let the MLT drain at the same rate until it's empty (and you've presumably reached you boil volume.)

And to continuing benefiting from your experience, what is your approximate strike water volume, wert volume and sparge water volume?

Much obliged!

 

[Natdavis777]

That's good to know. I may need to name my next brew "Copy Cat Saison" lol!

On the SABCO brew magic video it shows fly sparging and I gather the rate is about 1 quart/min or 1 gallon/5 min? Is that what you do?

And just to be clear (since I've only batch sparged before) once you've finished your mash, you drain the wert out at the rate you add the 180F water. Continue adding sparge water until the volume of wert from the mash plus the total volume of sparge water added will get you to your target boil volume, then turn off the sparge water and continue to let the MLT drain at the same rate until it's empty (and you've presumably reached you boil volume.)

And to continuing benefiting from your experience, what is your approximate strike water volume, wert volume and sparge water volume?

Much obliged!

I typically shoot for a rate of 1qt/ per minute.

After my mash is complete, I recirculate my wort for 10 min or so via the pump, but this is basically my vourloff. And correct, I drain the MLT at the same rate I sparge at. So 1qt/min for both sparge drain and MLT drain.

Once you have reached your pre-boil volume, you can stop collecting wort, regardless of how much is still left to drain in the MLT.

 

[Chefboubou]

I just brewed for the first time electric today! I added water at 180F (4.5 gal) in my MT, waited 10 min and it droped only to 175F. So I had to add cold water to get it where it needed to (164F).

Next time, I'll preheat the water at ~169F and it should be pretty close to where I want it to be.

Cheers!

 

[Natdavis777]

I just brewed for the first time electric today! I added water at 180F (4.5 gal) in my MT, waited 10 min and it droped only to 175F. So I had to add cold water to get it where it needed to (164F).

Next time, I'll preheat the water at ~169F and it should be pretty close to where I want it to be.

Cheers!

Good deal! Experience is the best way to dial in your system.

 

[Natdavis777]

And to continuing benefiting from your experience, what is your approximate strike water volume, wert volume and sparge water volume?

Much obliged!

Strike water volume is dependent on my grain bill. I typically use a ratio of 1.4qt/lb. So if I am brewing with 10lbs of grain, my strike water amount would be 14 quarts, or 3.5 gal.

I have a 1/2gal deadspace in my HLT/BK so I take that into account with my strike volume. So for the example above, my total volume going into my MLT for mashing would be 3.5gal (strike volume) + 0.5gal (deadspace volume) = 4gal total. Brew365 has a really good calculator that I acutally use when I make a recipe. It lets you plug in all the info and whatnot (I recommend keeping the "constants" unchanged) to give you the most accurate strike temp and volume. It even gives you your expected sparge volume and pre-boil volume.

There is a mathematical way of figuring this info out (not hard) but its way easier to plug these numbers in and have the Brew365 calculator figure it out. Other sites have good calculators as well.

Hope this helps

 

[CanAm]

Chefboubou - nice work on the electric. I've got an electric rig and was brewing indoors this winter. Much more comfortable - almost felt like I was cheating. Almost.

 

[CanAm]

Thanks Natdavis777 - definitely calling it Copycat Saison

I'm curious, why don't you recirculate throughout the entire mash?

 

[Natdavis777]

Thanks Natdavis777 - definitely calling it Copycat Saison

I'm curious, why don't you recirculate throughout the entire mash?

I do single infusion mashing, so if I were to recirc during the whole mash, say for a 60 min mash, my mash temp would drop out of the sacc rest range (per my experience). I dont direct fire under my MLT.

 

[Chefboubou]

Can-Am, that's why I converted to an electric set up! This winter has been so brutal, I brewed only once!

 

[CanAm]

Gotcha. I'll be hoisting a homebrew to you later this afternoon! Happy St. Patrick's Day!

 

[CanAm]

Chefboubou - that's a great reason. I've got an Auber PID controller I made for temp control and Brewer's Hardware element housing. Works like a charm. On the plus side of the cold weather, I cooled 11.5 gallons in under 15 minutes with my immersion chiller!

 

[Natdavis777]

Im putting a 240V outlet in my garage in the near future to go electric. I have been on the fence for awhile, but have made my decision. Im just tired of always having to run to menards to swap out a tank to ensure I have enough gas. And winter brewing sucks, especially in 0F weather.

 

[Chefboubou]

I went on the cheap side of an electric set up (as compared to the electricbrewery.com). I installed a 240V dryer outlet (30A), and I built a control panel with an Auber SSR manual control, and a single SSR. I didn't want to bother with a PID and the rtd it requires. I figured that since I used to control the gas burner manually, I could control my element manually as well! I only brewed once and honestly, I can't be happier. I bought two Camco 5500W element (1 for HWT and 1 for the BK).

I left a spot in the control panel for a PID though

 

[Chefboubou]

I should have put "cheap" between brackets since ti's not that cheap ;-)