How do YOU keep your cooler mash-tun as close to temp as possible?

[TheZymurgist]

Thats the thoughts I've had. I just mash a bit higher and expect a 1-3 loss. It doesn't matter to me, I was simply wondering if there was any cool ideas people did that would better my process, after all, we always want to improve. I have not missed my OG target so I've been pleased.

With that said, I have some reflective insulating bubble wrap (small bubbles)and aluminum tape that I'm going to make a nice 2 piece "outfit" to help. I'll be sure to bring it into the house like last time, just such a beach with a hurt wrist.

Out of curiosity, what is the largest grain bill those of you using the 10gal igloos?

I guess my question is whether it's actually an improvement, or whether it's innovation simply for the sake of innovation. Being able to hit your target mash temp is critical for consistency, and keeping close to that temp is important as well, but will anyone be able to tell the difference between a beer that was held at a constant mash temp vs. one that lost a degree or two, or even three?

Personally, I use a 10 gallon round cooler, and have never lost more than three degrees. I'm able to hit my mash temps consistently, and I'm happy with the final product, so I see no need to hold a perfectly constant mash temp. I guess that's just where I'm coming from. I'm certainly not trying to dissuade you, I'm just wondering if it's even worth the extra (albeit small) effort.

 

[oneandahalfshepherds]

I inject steam midway through and my cooler stays right on temp

 

[brewkinger]

You must be wrapping that cooler pretty tight to gain some "energy" heat

Actually, I have two possible theories:
The error theory that I measured temps. incorrectly.

The scientific theory proposed by PhD chemistry professor at Clarkson University:
If you have a cooler that is preheated with water that is hotter than mash temps (180 degrees in my case) then it absorbs heat (we call this pre heating)
Then dough in, bring temps down to 154 and then insulate and wrap the cooler, it is more than possible for the mash to absorb some of the energy stored in the cooler.
I have to take the man at his word, after all he does have the letters after his name.
I was willing to go with the error theory.

 

[MEPNew2Brew]

With a nod to Land o Lincoln for the suggestion, I used tinfoil to address heat loss. I have a 72 quart Xtreme, pre heat, and do not open during mash. Lost less than 1 degree. Before using tinfoil, I was loosing 4 - 5 degrees.

 

[IanJ]

I've had trouble with my 10g Rubbermade from Lowes. The lid isn't insulated, so I was losing a good amount with test 3g batches, which was kind of a let-down. Recently I've been experimenting with all sorts of materials, wrapping it in reflective emergency foil, pillows and blankets, and was able to keep it to a ~3 degree loss for a 75 minute mash indoors during my last 5g brew.

Something's gotta give! Need a better solution for smaller batches at the very least. Not sure if filling the lid with foam is worth the risk.

 

[govner1]

I've had trouble with my 10g Rubbermade from Lowes. The lid isn't insulated, so I was losing a good amount with test 3g batches, which was kind of a let-down. Recently I've been experimenting with all sorts of materials, wrapping it in reflective emergency foil, pillows and blankets, and was able to keep it to a ~3 degree loss for a 75 minute mash indoors during my last 5g brew. Something's gotta give! Need a better solution for smaller batches at the very least. Not sure if filling the lid with foam is worth the risk.

I use a 7 gal Rubbermaid for 3 gal batches. That's all I do. I preheat w/ 120-140 water while my strike water gets to temp. Then I dump it in a bucket for cleanup later. I usually stay within 1-2 degrees of my target temp.

 

[wilserbrewer]

Heat loss will be dependent on the percentage of the volume filled in the cooler...for smaller batches I feel a smaller cooler is better.

Fwiw
Cheers

 

[Esmitee]

Does no one else use the foil on top of the grain bed trick?

Never tried this method yet, Next batch I will. Seems like I'm always fighting the mash temp! I do use an older cooler too. I brew outside and I'm to lazy and the cooler is to heavy to cart UP and indoors. I made this ( reflextive bubble wrap) cooler wrap and sometimes also use a blanket with the wrap.

 

[brewkinger]

If I have room, I use a circular piece of Reflectix insulation that I cut to fit my cooler. Most batches I have the cooler maxed out with 10-12# of grain and 1.3 grist ratio.
I also drilled 1/4" holes in the lid and filled my cooler lid with foam insulation and then epoxied small plastic caps to cover the holes.
I screw the lid on as tight as I can get it.

 

[EmDubeu]

what about those of us who are using a 15.5 gallon sanke as a mash tun? How are you keeping your mash at temp for 60 minutes?

 

[masskrug]

In Florida, this is not much of an issue. I get my temp locked in and close the lid. I usually only lose about 1 degree.

Now, on the issue of cooling, you up north have the upper hand. Choose your evil.

 

[mrkrausen]

In my 10 gallon mash tun I usually only lose 1-2 ºF with preheating my tun and a folded up blanket over the lid. I've only done 2 batches so far in the 5 gallon tun I just built, but I lost about the same the first batch and this batch I brewed today I lost 5 ºF. I'm not sure what caused such a big drop this time. I think I will try the foil or maybe the insulation on top of the grain bed next time though.

 

[Hamaki]

what about those of us who are using a 15.5 gallon sanke as a mash tun? How are you keeping your mash at temp for 60 minutes?

I've got my sanke MLT wrapped with one of those cheap blue foam pads you put under a sleeping bag. It helps some but I still have to start out with a stiff mash and plan on adding boiling water a couple of times during the mash to keep in the neighborhood I want. My mashes generally fluctuate by 2 - 3 degrees. I try to start about a degree higher than my targeted average. I want to go to a herms setup to stabilize things but no pumps for now

 

[opiate82]

So I had a big styrofoam box out in the garage. I cut a circle out of it big enough to fit snuggly inside my 10gal Home Depot Cooler Mash tun then wrapped it up in a food-safe bag and zip-tied it shut. The circle is probably about 2" thick and it is your typical white styrofoam used for packing or as disposable coolers.

Brewed a Blonde with just 9lbs of grain. Grain + Water took up less than 1/2 of the space in the tun. I had recently discovered I was losing a lot of heat on small beers like that (9 degrees on my last one). With my styrofoam circle resting just above the grain bed I lost less than 1 degree. Nothing changed in my pre-heating or dough-in methods, everything was exactly the same other than the, I guess you would call it a false-top.

 

[user 19629]

Heat loss will be dependent on the percentage of the volume filled in the cooler...for smaller batches I feel a smaller cooler is better.

Fwiw
Cheers

Yea, or if you don't have a smaller cooler, just use mash thinner.

 

[Gixxer]

So I had a big styrofoam box out in the garage. I cut a circle out of it big enough to fit snuggly inside my 10gal Home Depot Cooler Mash tun then wrapped it up in a food-safe bag and zip-tied it shut. The circle is probably about 2" thick and it is your typical white styrofoam used for packing or as disposable coolers. Brewed a Blonde with just 9lbs of grain. Grain + Water took up less than 1/2 of the space in the tun. I had recently discovered I was losing a lot of heat on small beers like that (9 degrees on my last one). With my styrofoam circle resting just above the grain bed I lost less than 1 degree. Nothing changed in my pre-heating or dough-in methods, everything was exactly the same other than the, I guess you would call it a false-top.

.
That's what I do. I got a few sheets of styrofoam from lowes and cut to fit inside my round cooler, And it rests right on top of the mash.

 

[hmmmbeer]

Brewed a small batch yesterday (17lbs grain bill) and I held my temp. over a 60 min mash to only 1 degree loss. I made my insulation wrap, put a blanket on top of it and brought it into the house. Win in my book! I forgot the aluminum foil until it was too late. Thanks for the advice from so many people, LOVE THIS SITE!

 

[Gamer]

Try putting aluminum foil on top of the mash.
I switched from a 10 gallon to a 7 gallon water cooler and there is a minimum of space between mash and lid.. 3-4 inches of air doesn't allow much heat to dissipate into the air. Lose 1 degree if that and I stir mash every 15 minutes over 60 minutes.

 

[ghohn]

Preheated MT + a thinner mash 1.75 qt/lb on double batch. Rock solid.

 

[Yesfan]

I just shoe-horned a Bayou Classic kettle into a round cooler.*

Last few batches I did I may have lost from .5F-1.0F in a 60 min mash.


* idea from member Ben the Brewman



EDIT: I really don't understand how these cooler manufacturers aren't considering this idea of going with a stainless liner. If I thought I could buy a 15 gallon cooler, round or rectangular, with a stainless liner, I'd buy right now.

 

[Btaz]

I placed 1/4" ridged foam (left over from my fermentation chamber build) over the mash. Prior to that I would lose 5degF during a 60 min mash. Now I might change 1degF. Oh and I have a huge mash tun and it works the same with 5 Gallon batches too

View attachment 1428211416490.jpg

 

[Bamsdealer]

I've learned to become less anal about the whole brew process. If it's a batch with little heads pace or its hot outside I done worry about it. If it's cold out or I'm brewing a 1.045 beer I'll mash a degree or two higher to account for temp loss.

 

[KartRacer54]

I have been brewing for years and have since gone to AG a few years ago but have never been able to hold my mash-tun AT temp. In the pas I have just accounted for the 2-3 degrees that I lose so if I need to hold 153 I'll mash at 156. I am using a cooler as my mash-tun and thought of using a fermentation band(for a bucket) or even plugging in a heater blanket and just wrap it like a baby. That just gave me another idea, heating pad under the cooler should help too... I might try the heating pad and heated blanket this weekend and see how it does. I'll keep you posted on the outcome. BTW, I'm talking about when it gets cold outside(as I brew in my garage that isn't heated).

How do you keep your temp. close?

Thanks for any ideas!

I use a Home Depot round cooler. I preheat the tun by filling with tap water, right now it is about 110 degrees. I empty that just before I add my strike water. After adding grain using BeerSmith, my temps are within 1/2 degree, it usually raise 2 more degrees and with lid on will stay at that temp for the full hour even when I brewed this winter at 35 degree ambient temp.
The key is preheating the tun so it does not cool off during the mash.

 

[masaba]

I haven't had any trouble with heat loss whatsoever. I have a 62 qt Coleman Extreme cooler. I pre-heat it for about 20 minutes, add mash water, dough in, and close it. I have done 6 beers like this so far and the most heat loss I have experienced is 1 degree over a 60 minute mash.

And also, I seriously doubt that losing 2 degrees over the course of a 60 minute mash is going to affect the beer whatsoever.

 

[RichBrewer]

Don't forget, as I have stated before, pour your strike water at 5 to 10 degrees warmer than your target temperature and then let it cool to your target before adding grains.

 

[KartRacer54]

Don't forget, as I have stated before, pour your strike water at 5 to 10 degrees warmer than your target temperature and then let it cool to your target before adding grains.

If mash tun has not been preheated all of that cold surface will pull temps down several degrees. Learned from experience ( the hard way).

 

[Ski12568]

I just shoe-horned a Bayou Classic kettle into a round cooler.*

Last few batches I did I may have lost from .5F-1.0F in a 60 min mash.


* idea from member Ben the Brewman



EDIT: I really don't understand how these cooler manufacturers aren't considering this idea of going with a stainless liner. If I thought I could buy a 15 gallon cooler, round or rectangular, with a stainless liner, I'd buy right now.

What size cooler and pot did you use?

 

[Yesfan]

What size cooler and pot did you use?

The cooler is the typical Home Depot 10 gallon. The pot was a Bayou Classic. It's just a generic kettle with no volume markings, etc. I drilled the hole for the spigot. I believe the pot model is the 1044.

 

[Ski12568]

The cooler is the typical Home Depot 10 gallon. The pot was a Bayou Classic. It's just a generic kettle with no volume markings, etc. I drilled the hole for the spigot. I believe the pot model is the 1044.

Thank you

 

[LandoLincoln]

If mash tun has not been preheated all of that cold surface will pull temps down several degrees. Learned from experience ( the hard way).

Two degrees, in my experience. Not really worth the time.