Is it possible for a cooler to be TOO big as a mash tun?

[berley31]

Been trying to assemble a mash tun out of a cooler, your standard SS braid set-up. One of the coolers I've seen is the Coleman XTreme 70 quart... now, I know this is a huge cooler. The dimensions are roughly 24" long x 10" wide, 12" high.

Would this be too big when you're looking at a 'standard' batch of 5 gallons, such as 1.050-1.060 beer? Or even if you wanted to do something lower, like a Mild.

Also, does anyone just use the cheaper, 48-quart regular Coleman coolers? I was just wondering if it's actually worth it buying a more expensive one, or if the 25$ ones hold the heat constant just as well.

 

[david_42]

I've got the 48 qt IceCube and it's worked just fine, even for PM. Unless you are planning on doing 10 gallon batches of big beers, 48 is probably plenty. I'll note that I do thin (5:1 to 7:1 by weight) mashes and batch sparge.

 

[BeerPressure]

I use that cooler and it holds temps well with as little as 10.5 lbs of grain, but the more grain you mash the better it holds a temp.

 

[wilserbrewer]

Also, does anyone just use the cheaper, 48-quart regular Coleman coolers? I was just wondering if it's actually worth it buying a more expensive one, or if the 25$ ones hold the heat constant just as well.

I've used the inexpensive coleman 48 and was able to hold temps. The key is preheating.

While you could likely use a 70 qt, I think Iwould findit inconveniently large.

 

[lackey2000]

I use one of those cheap blue Coleman Ice Cubes and I have difficulty maintaining the mash temp. I injected the lid with expanding foam, preheat, place an old heating pad underneath and wrap it with blankets. Should have just bought one that worked first time around.

I just recently found one of those orange beverage coolers at a local thrift store for $5.99. Looks like crud on the outside but inside is spotless. Think a switch is in my future.

 

[DavidP]

Also keep in mind that larger/wider coolers will have a shallower grain bed resulting in poorer filtration.

 

[Homercidal]

The more empty space you have, the faster it will cool. I don't know if it's enough to worry about, but with more hot water, you have more thermal mass, and therefore less heat loss.

 

[Shepherd5]

A general rule is that you should have at least 6 inches of grain bed in your mash tun to be most effective. If I remember correctly, this is what John Palmer advises.

 

[Synovia]

A general rule is that you should have at least 6 inches of grain bed in your mash tun to be most effective. If I remember correctly, this is what John Palmer advises.

That's not relevant to batch sparging though, and I think more people batch sparge than fly sparge.

 

[wilserbrewer]

" Is it possible for a cooler to be TOO big as a mash tun? "

IMO, yes. I have no desire to schlep a 70 qt cooler out to the back yard and dump a lil o mash of 14-16 pounds. More tool than you need for me.

 

[niquejim]

The 165qt cooler is too big for most beers, but 70 qt if you're batch sparging and think you may like to do 10 gallon batches or big(1.110 or bigger) will be fine. The 48qt is pushed to the limit with a 5 gallon Barleywine

 

[throwbookatface]

I just wanted to point out that if you have problems with heat retention/getting the cooler's insulated temp up to ~150 degrees, just pre-boil some sanitary water, throw it in the cooler, then pour it out before filling your tun with mash. It's the same strategy campers use for keeping thermoses hot/cold longer, by bringing the insulated layers to the right temp without having to use heat from your intended liquid to warm it up first.

 

[DavidP]

That's not relevant to batch sparging though, and I think more people batch sparge than fly sparge.

I've always been confused by this thinking... both styles of sparging need a good filter bed to produce clear wort. The minimum height makes for a denser filter towards the bottom.

 

[Myke_J]

I use the 70qt Xtreme and love it. I've used it for 5gal batches as small as 10#'s and 10gal batches up to 32#'s. I always preheat by adding my strike water at around 185 and letting it sit for 20 mins or so. Then I will stir until I get the water down to my strike temp and dough in. The most temp loss I've seen during a 90min mash was about 1.5 degrees and it was around 36 degrees outside when I was doing it. I use a steel braid with stainless wire coil inside. When I started using this cooler I was batch sparging, but found my efficiency to be really random. I had got anywhere from 60-80%, but couldn't get any consistency. I've started flysparging and am now getting 85% efficiency consistently with no change to the mash tun. I like to do a nice slow sparge. With my porter it was 70 mins from starting the vorlauf to reaching my pre-boil volume of 14gals.