Ideas for insulating a cooler mash tun

[MrBJones]

I'm thinking of a round piece of thick Styrofoam (or something like it) floating on top of the grain bed to help reduce heat loss. What do you think?

Any other ideas to increase a cooler's ability to retain heat?

 

[kevin58]

So you want to insulate your insulated cooler? For starters, I wouldn't let anything Styrofoam float on top of my mash. You can wrap your cooler with something to hold heat better but typically the reason we use insulated coolers is because they inherently hold temperature quite well for the period of time that we require.

 

[BoozeMedic]

So you want to insulate your insulated cooler? For starters, I wouldn't let anything Styrofoam float on top of my mash. You can wrap your cooler with something to hold heat better but typically the reason we use insulated coolers is because they inherently hold temperature quite well for the period of time that we require.

This seems like a decent idea if you want to reduce heat loss to head space. Aluminized bubble wrap cut to just barely fit.

 

[RPh_Guy]

I wrap my cooler mash tun in a blanket. Folded towels under it and on top.

I stabilize the temp before dough in.

Keeps it pretty cozy.

 

[str1p3s]

I put fleece blankets under and on top. I cut a circle of Styrofoam and sealed in a slow cooker liner and did that for a few batches but it seemed like it was more trouble than it was worth.

 

[mongoose33]

I've been doing what OP suggested but as a mash cap to limit oxygen ingress to the mash. I'm about 90 percent convinced it's food safe to do that, but not quite. I got some 18" wide saran wrap and covered it with that, some foil underneath that, and put a handle on it so I could easily remove it.

 

[WFox93]

The most I've ever even thought about doing to my cooler mash tun is painting it black and stealing some heat from the sun to help it maintain its temperature better. Not sure it would help all the much but it definitely would make my coolers look more purpose built rather than like the home depot water coolers they are.

 

[RPh_Guy]

I hook up about 5 space heaters each on a temp controller with the probe against my mash tun and just bring my brewing room to my correct mash temperature a day in advance.

 

[divrack]

The most I've ever even thought about doing to my cooler mash tun is painting it black and stealing some heat from the sun to help it maintain its temperature better. Not sure it would help all the much but it definitely would make my coolers look more purpose built rather than like the home depot water coolers they are.

Don't black bodies radiate heat more effectively? Some physics thing I struggle to understand clearly

 

[Kent88]

How about just an appropriately sized cooler with the lid that came with it?

I use a 3-gallon cooler, it holds heat pretty well because I always try to fill it with as much grain as I can. Sure I'd like a 5-gallon so I could make doppelbock, barleywine, strong ales, etc., but I don't need my mash to warm up all that extra cooler material for my lower gravity beers, and I don't need a ton of headspace to lose heat in.

Know your typical batch size, know the weight of your typical grain bill, plan accordingly. If you still need insulation I would think blankets would be the way to go.

 

[divrack]

Put it inside a bigger cooler..
Although then you'll want to insulate that. So you'll need an even bigger cooler. And so on.

 

[RPh_Guy]

Don't black bodies radiate heat more effectively? Some physics thing I struggle to understand clearly

Iridescent actually has the highest radiation coefficient, followed by red, which is where we get the phrase "red hot".

 

[RM-MN]

I'd go the opposite way. Instead of trying to avoid all heat loss for an hour, I mill my grains finer so the conversion takes less time. You may be chasing a problem that doesn't exist. Get a refractometer so you can sample the gravity of the wort quickly and test for the conversion over time. You may find that the conversion is done in much less than the 60 minutes you are trying to hold the temperature for.

 

[GPP33]

I don't really have anything to add regarding further insulating a cooler but how much of a temp drop are you guys actually seeing in a cooler? I mash in a converted keg with no insulation and drop 2 degrees over an hour, probably less than 1 degree in the time it actually takes to complete conversion. If you brew outside in Alaska in January this might be a problem but even during the winter in Co in my garage it's a non issue.

 

[Dade0]

I don't really have anything to add regarding further insulating a cooler but how much of a temp drop are you guys actually seeing in a cooler? I mash in a converted keg with no insulation and drop 2 degrees over an hour, probably less than 1 degree in the time it actually takes to complete conversion. If you brew outside in Alaska in January this might be a problem but even during the winter in Co in my garage it's a non issue.

I use a round igloo cooler and only see 1degree of loss in a 1 hour mash.

Sent from my XT1575 using Home Brew mobile app

 

[divrack]

Iridescent actually has the highest radiation coefficient, followed by red, which is where we get the phrase "red hot".

Look, I'm not claiming nothing about nothing, but you'd better not say that around my mate Kirchoff's place, he makes the laws around there...

 

[John Eberly]

What Dade0 said - round 10 gal Igloo holds within a degree for 75 minute mash for me. Just keep the kid on.

 

[John Eberly]

Lid that is

 

[Spartan1979]

Use of of these: http://www.michaels.com/floracraft-...ar_M10219979_color=White#q=styrofoam&start=15

I wrapped in it tinfoil, place it in a garbage bag (that I later use for spent grains) and then another sheet of aluminum foil between the bag and the grain. I had another one that after wrapping it in aluminum foil, I placed right on the grain, but it leaked and got moldy.

 

[str1p3s]

In the winter (Ohio) I find that I lose a few too many degrees if I don't put a fleece blanket on top. It's probably fine in the summer, but now I just do it every time as a habit.

 

[mongoose33]

The best success I've had with a cooler mash tun was to first pre-heat it with a gallon of boiling water (left in there for 10 minutes or so), then after the dough-in, wrap it with a quilt. A quilt, a moving blanket, a sleeping bag--the trick is to isolate the cooler itself from ambient.

I have even gone so far in the winter to put the cooler on a heat mat so the bottom isn't having the heat sucked out of it by a cold surface on which it's sitting.

 

[jpakstis]

I’ve found that “priming” the cooler with some boiling water seems to help flatten out the temps both before and after doughing in. I don’t do anything else to insulate (other than put the cover on of course)! Even in the middle of winter when it’s like 10 degrees out I’ve only lost like 2-3 degrees during the mash. I BIAB full volume so maybe the larger water volume helps keep it at the same temp?

 

[Soulshine2]

I'm thinking of a round piece of thick Styrofoam (or something like it) floating on top of the grain bed to help reduce heat loss. What do you think?

Any other ideas to increase a cooler's ability to retain heat?

whats wrong with hot water pre-heating the mash tun and then closing the lid once you start mashing. I've had to actually raise my lid a while to cool it off before worrying about trying to get more heat to it. losing 5 degrees in an hour isnt going to matter that much

 

[Soulshine2]

How about just an appropriately sized cooler with the lid that came with it?

I use a 3-gallon cooler, it holds heat pretty well because I always try to fill it with as much grain as I can. Sure I'd like a 5-gallon so I could make doppelbock, barleywine, strong ales, etc., but I don't need my mash to warm up all that extra cooler material for my lower gravity beers, and I don't need a ton of headspace to lose heat in.

Know your typical batch size, know the weight of your typical grain bill, plan accordingly. If you still need insulation I would think blankets would be the way to go.

only 3 gallons...I use a 42 quart Igloo Cube , holds more than enough milled grain plus the water to mash and way more than insulated to hold the required heat for an hour.