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Pre-heating a mash tun..

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This is all a bunch of great food for thought! I'm currently doing AG with BIAB, but I plan on moving to a mash tun soon, and I want to be well educated before giving it a try. I have a SS sanke keg that I could turn into a MLT. I like the sounds of the Igloo cube, though. I'm not sure which one I will use yet.. I'm guessing if I make one out of the keg it can double as a kettle.. Choices, choices!

Well you can fit a 10 gallon batch of grain in an igloo cube no prob, and then boil it in that sanke. Sounds like a plan to me. Now I'm jealous.
 
Well you can fit a 10 gallon batch of grain in an igloo cube no prob, and then boil it in that sanke. Sounds like a plan to me. Now I'm jealous.

I started my keggle build yesterday. Here's what it looks like. I just need to get valves and polish it up...
IMG00508-20120117-1524.jpg
[/IMG]

Now I'm also going to shop around for an igloo cube..
 
I have a Coleman Xtreme 52 qt MLT. I bring about a gallon of water to a boil on the stove then throw in it the MLT while the strike water is coming to temp. Drain the water right before I put my strike water in. I then use Beersmith to tell me my strike temps, and it hits my mash temp dead on every time! Easy day!
 
I use a converted igloo water cooler and just fill it up with 150 degree tap water while I'm heating my strike water. Works for me.
 
I came here because i"m having major issues with my mash temps. Not my strike temps, mind you. [As others here do, I heat my mash water 10-12 degrees beyond my target strike temp and let the cooler preheat about 10 minutes. Then I wait and/or stir until the water reaches strike temp, and I dough in.]

I use a 52 qt rectangular Coleman XTREME, and I'm losing 6-7 degrees over a 60 minute mash! WHY?!!?

Er... I mean, why? Please?
 
Judochop said:
I came here because i"m having major issues with my mash temps. Not my strike temps, mind you. [As others here do, I heat my mash water 10-12 degrees beyond my target strike temp and let the cooler preheat about 10 minutes. Then I wait and/or stir until the water reaches strike temp, and I dough in.]

I use a 52 qt rectangular Coleman XTREME, and I'm losing 6-7 degrees over a 60 minute mash! WHY?!!?

Er... I mean, why? Please?

I'd try preheating for longer. Fill the cooler with tap water as hot as you can get it and let it sit for 1/2 hour or so. If you're losing that much heat I'd also wrap it in a sleeping bag or two.
 
I do. I have a cooler. I usually just turn on the hot water tap and fill it with a couple gallons of hot tap water, then seal it up and let it sit til I'm about ready to mash in.
 
I'd try preheating for longer. Fill the cooler with tap water as hot as you can get it and let it sit for 1/2 hour or so. If you're losing that much heat I'd also wrap it in a sleeping bag or two.
I thought I was getting the cream of the crop with this coleman xtreme. I didn't think it'd take that long.

Calling all Xtreme users, for how long do you preheat?
 
One thing i noticed with my cooler, the part of the lid with the handle indentation didnt seal too well so i put a large heavy object the length of my cooler on top of the lid to help seal. I also throw a sleep bag doubled up over the cooler. It now holds temps great.
 
One thing i noticed with my cooler, the part of the lid with the handle indentation didnt seal too well so i put a large heavy object the length of my cooler on top of the lid to help seal. I also throw a sleep bag doubled up over the cooler. It now holds temps great.
I feel pretty good about my seal. It takes a good hearty push just to close.

How long do you preheat?

I will try some external insulation next time, but I feel like 6-7 degrees over 60 minutes is a pretty big loss. Hard to imagine a sleeping bag will make the difference.
 
I preheat about 5 to 10 minutes. I just over heat my strike water, pre heat then stir it till it gets to the temp i want.
 
Depends on the temp outside, i brew in the winter in the garage here in wisconsin. Now ill prob heat to 10 degrees over for about 5 minutes. Then stir it down to temp.
 
I am setting up for my first AG, using a 5 gal round igloo cooler. When doing the pre-heat, then adding the grain and strike water, is it better to add the grain into the hot water or to drain the cooler - add the grain and put the water back in.
Thought I had read somewhere that it was better to slowly add the water to the grain (letting the grain cool the water) than to add grain to the hot water (exposing the first bit to water that was too hot).
 
Probably better for your mash to mix grain and water simultaneously. But that does add an extra step. Many many foiks just add grain to the hot water and get great results.
 
I thought I was getting the cream of the crop with this coleman xtreme. I didn't think it'd take that long.

Calling all Xtreme users, for how long do you preheat?

I preheat with water about 15* over just to be safe, but I take notes every time. I use a 2 qt pitcher to pour my 15* higher strike water and pour it down around all the sides. I lose about 6-8* tops. I stir down til temp. but now that I know I am always like 6-8 degrees over I am just going to start doing 8 over.

In my coleman xtreme 52, i throw a blanket over it and I don't lose a degree at in the grain area. If I have a thin mash and there is a clear amount of wort on top that will be a little cooler, but only a few degrees. the main portion in the grain is the correct temp. Stir it all up and it reads a degree or two low
 
Wondering has anyone measured the efficiency differences between mashing thinner and losing a degree vs. mashing thicker and not losing? I've been mashing thinner (1.3-1.4) for more soluble sugars, since I was BIAB...now I have hose braid and was thinking perhaps I would mash thicker, add a mashout addition to thin, then drain, batch sparge.
 
I came here because i"m having major issues with my mash temps. Not my strike temps, mind you. [As others here do, I heat my mash water 10-12 degrees beyond my target strike temp and let the cooler preheat about 10 minutes. Then I wait and/or stir until the water reaches strike temp, and I dough in.]

I use a 52 qt rectangular Coleman XTREME, and I'm losing 6-7 degrees over a 60 minute mash! WHY?!!?

Er... I mean, why? Please?

I've progressed quite a bit in my process since first posting this thread. I also have a 52 qt Coleman Xtreme that I use as my MLT now. I pre-heat it with about 2 gallons of 185F water that I drain and re-use as sparge water. I only let it pre-heat for 15-20 mins. Two weeks ago I mashed an Imperial Stout in it for an extended 3 hours. I mashed in at 156F and only lost 6*F in that time. I did employ a few tactics to maintain the temps by wrapping the cooler with saran wrap where the lid meets the body. This way the hot, steamy air can't escape as easily. I also covered it with a couple blankets...
 
Wondering has anyone measured the efficiency differences between mashing thinner and losing a degree vs. mashing thicker and not losing? I've been mashing thinner (1.3-1.4) for more soluble sugars, since I was BIAB...now I have hose braid and was thinking perhaps I would mash thicker, add a mashout addition to thin, then drain, batch sparge.

I usually mash thick (1.15-1.25), do a mash-out, and batch sparge and get about 75-78% efficiency. Tomorrow I'm going to mash thin (1.34) and skip the mash-out, then batch sparge. I'm curious to see how it changes my efficiency, if at all..
 
I have the 103 extreme and preheat with around 15 gallons of ~140 tap water. I do this before I start heating the mash water and milling grain so ends up being around forty minutes, and I never have more than a degree or two change over sixty to ninety minutes. I did notice if I left the cooler on the ground it lost more so now put it up on a table.
 
I just put my water in once, little higher than your strike temp let it preheat then stir it so it cools down to your strike temp and then dump in your grains. Why are some of you preheating then draining then putting your strike water back in again? not knockin, just curious.
 
I just put my water in once, little higher than your strike temp let it preheat then stir it so it cools down to your strike temp and then dump in your grains. Why are some of you preheating then draining then putting your strike water back in again? not knockin, just curious.
That's how I do it too. I put my strike water in at 10° over strike temp. Close the lid & wait until it reaches strike temp. (Usually about 10 minutes). I don't like wasting water.
 
I use a 10 gallon igloo.I just hold back 1 quart of my strike water.Heat the rest to
180 pour it in MLT ,swirl and dough in.If the mash temp is to high I slowly
add the remaining 1 quart of cold strike water until I hit my exact mash temp.Works
everytime.

cheers
 
I have found that three charcoal briquets wrapped in aluminum foil works great to preheat the MT.....works best for rauchbier...sorry just being silly, but WOW! Six pages, 55 posts to get the mash tun preheated, at this pace it will take weeks to pitch some yeast...:mug:
 
I just put my water in once, little higher than your strike temp let it preheat then stir it so it cools down to your strike temp and then dump in your grains. Why are some of you preheating then draining then putting your strike water back in again? not knockin, just curious.

To be honest, I haven't done it like this because I worry my MLT will absorb too much heat and leave my strike temp too low. I just haven't experimented enough to know. I guess on my next batch I'll give it a try. Maybe I'll start around 12*F higher just in case...
 
I have a 60qt ice cube. I mounted a hot water heater element in the side of it. I plug it into a ranco, I plug the ranco into a timer. I fill my mash tun with strike water the night before I brew. An hour before I wake up the water starts heating. When I wake up my mash tun is pre-heated and my strike water is ready to go. I just add grain...
Folks mashing in kegs could do this the old fashioned way.
:rockin:
 
I usually mash thick (1.15-1.25), do a mash-out, and batch sparge and get about 75-78% efficiency. Tomorrow I'm going to mash thin (1.34) and skip the mash-out, then batch sparge. I'm curious to see how it changes my efficiency, if at all..

What were your findings? I AGAIN got low efficiency on my oatbier last weekend. In the 60's. I mashed around 1.25 and did a mashout, vorlauf, drain, sparge, vorlauf, drain...but I noticed my absorption was way higher, made my volume lower. I think the deadspace in my tun affected volume, too. When I realized volume was low I should have added more sparge water and done another batch sparge. As it was, I added water to the boil which had 0 sugars in it. Thinking that's the reason.
 
Similar to others, this is my process. I use a 10 gallon Rubbermaid Round Cooler:

-Cooler comes inside the house from the garage the night before brewing if its cold.

-Use beersmith to determine strike water temp. I check grain temp and use zero weight for cooler, since Im heating it.

-Strike water heated 8 to 10 degrees above needed temp.

-Fill Mash Tun and cap.

-Wait 15 to 20 minutes. Open and stir until instaread thermometer shows required temp.

-Add grains slowly while stiring. Mix well. Check Temp. Cap cooler.

-Place a bed pillow on top of cooler and cover with a blanket. Wrap metal valve with part of blanket. These are the two places you loose the most heat (Lid and valve).

With this method, I usually nail my temps and only loose a half to one degree after 60 minutes.
 

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