Mash Tun heat loss problem

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captgus

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I was hoping that I could get some suggestions. I originally purchased this as my brew pot, with the intention of using the 5 gallon igloo for my mash tun.

http://www.northernbrewer.com/shop/...tles/megapot-with-ball-valve-brewmometer.html

It worked great as a brew pot and clean up with a little Bar Keepers Friend was always a breeze. The igloo as a mash tun was great at hitting and maintaining my mash temps but I always seemed to have problems with grain getting under the false bottom, more often than not leading to a stuck sparge. I dealt with the stuck sparge on a case by case basis but it became painfully obvious that anything of a higher than average gravity was pushing the limits of my 5 gal igloo. The first of the year arrived, as did a used bourbon barrel and I knew that I wanted to brew a barley wine and age it in the bourbon barrel but the conundrum was fitting 24+ LBS of grain in a 5 gallon mash tun. Long story short, I borrowed a friends brew pot and used mine as the mash tun since I already had the false bottom. It worked like a charm, I didn't have to fiddle with the ball valve fitting and leakage, I didn't end up with a stuck sparge and after a quick vourlaf, I had clear wort! Perhaps the clearest wort to date, I was smitten. I did notice a little drop in mash tun temp but not a great deal and assumed it would just leave me with a higher level of fermentable wort.

In hind sight, I now realize that the temp drop wasn't that great because, or rather at least I theorize, was due to me pushing the limits of 10 gal mash tun, it was filled to the brim. Now, when I attempt to brew using the 10 gal brew pot with the false bottom as my mash tun, I'm finding that the temps are dropping and dropping fast. I've been getting around this by periodically turning on my burner and recirculating the wort below the level of the false bottom. It works but it's labor intensive, doesn't allow me to mash at one temp for very long and I worry about hot side aeration.

Does anyone have any suggestions on how I can further insulate the brew pot to get around the temp losses? Am I over thinking the hot side aeration issue and should I just continue with method of adding heat intermittently? Any help would be greatly appreciated.
 
Yea 5 gallon igloo coolers are way too small for many 5 gallon batches...24lbs of grain is beyond even what the 10 gallon igloo's can really hold..or VERY close depending on how thick you mash.

That said to your question go buy Reflectix at your local home depot/lowes.

You then basically wrap your pot (except the bottom obviously) with it.
One way is to make an entire shell for it, get to your temp, lift the pot into this shell, throw the top half of the shell on and let it sit. Think like a plastic egg...the fit should be close but doesnt need to be super snug so you can get it in and out easy.

Or the more common easier way is you could just wrap the sides and make a top for it and leave the bottom bare so that you can just keep the reflectix on while your heating and using the pot.

A few examples of what i mean
116418d1366341684-mash-tun-reflectix-wrap-forumrunner_20130418_202119.jpg



And a ton more from Google Images
https://www.google.com/search?q=Bre...fp=2e8aebdb56399be4&biw=1680&bih=946&imgdii=_
 
I BIAB so keeping my mash temps in the kettle was a challenge at first.

I got one of these things. Got mine free but they sell them at Home Depot for like $20.

attachment.php


Here's a link:

http://www.homedepot.com/p/Frost-Ki...ter-Blanket-R3-5-SP90A/100170479#.Udcc9PjD_b1

It's a water heater insulation mat blanket thingy. Wrap this around your pot and secure with bungies. If you have extra material, try to cover the top too. I destroyed an old Styrofoam cooler to cover the top of mine.

I never lose a single degree, even with a 90 minute mash.

Just make sure you cut the flame before you strap this on.

A lot of folks have had good success using blankets, sleeping bags, and really anthing that makes good insulation.

EDIT:

Ok Fuzze has a much better looking version of what I do.
 
I made a jacket similar to the one above when I was using a pot. It worked pretty well and I only lost a couple degrees over the hour. I also wrapped the kettle in a down sleeping bag to insulate it a bit further.
 
The real trick is covering the top. When I first used my insulator thing I still lost a few degrees.

Then I made a 3" thick Styrofoam top for mine and haven't lost a degree yet. In fact, my last session I actually went up a degree!!
 
Yea 5 gallon igloo coolers are way too small for many 5 gallon batches...24lbs of grain is beyond even what the 10 gallon igloo's can really hold..or VERY close depending on how thick you mash.

That said to your question go buy Reflectix at your local home depot/lowes.

You then basically wrap your pot (except the bottom obviously) with it.
One way is to make an entire shell for it, get to your temp, lift the pot into this shell, throw the top half of the shell on and let it sit. Think like a plastic egg...the fit should be close but doesnt need to be super snug so you can get it in and out easy.

Is this the stuff that looks like it has tiny plastic bubble wrap sandwiched between the reflective material? I tried some of this with the Saison I brewed on Wednesday. Granted it was only wrapped around once but as soon as I applied heat, it began to warp and the portion that was closest to the bottom began to melt.

I now see the errors in my methodology. If i were to try this next time, perhaps a few more layers, secured with bungee cords and add it after I've mashed in?
 
I started mashing in a keg glue and tried to come up with a cheap way to insulate instead of using refletex...which ended up not working at all. Next time I threw a sleeping bag over the entire keg hole and the temp stayed within 2 degrees the entire time. If you have a sleeping bag laying around give that a shot
 
as for your melting problem I forgot to mention that I wrapped all the parts that were going to come in contact with a lot of heat in heavy duty ductape which can withstand up to 300F
 
Ok, sounds like you have a direct fire RIMS system, just without the typical automated control system.
For the hot side aeration I would not worry, mash temp is far more critical, and many brewers stir their mash regularly. I seem to recall an interview with someone like Dr. Bamforth saying hot side aeration problems are basically a myth as far as practical concerns.
 
Well the recirculating isn't automated, unless you count me standing at the end of a ball valve, stainless pitcher in hand, draining the wort under the false bottom and pouring it back in and then stirring every so often. ;)

Thanks for the tip on Dr. Bamforth, I'll be giving this a listen tonight. Perhaps it will give me some time and peace of mind until I can get a semi permanent solution nailed down, as I have a Belgian Blonde on tap for this Saturday.

http://thebrewingnetwork.com/shows/475
 

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