Optimal Cooler for MLT

[BarefootFriar]

I've got a 5-gallon Rubbermaid drink cooler, and it works okay. Actually, I have to work to keep temps from rising during the mash. However, it's not big enough, and since I like brewing bigger beers, I need a bigger MLT.

I was just going to trip lightly down to "big orange" and buy a "big orange" 10 gallon drink cooler, but then I got to thinking. Is there another shape that would actually be better? For instance, I've already got a rectangular, 15 gallon cooler that I could easily convert*. That would definitely give me more room, but at the expense of grain bed depth. Of course, for small grain bills I can use my current MLT, if the grain bed is too shallow.

One of my specific questions is what is the advantage to a 10 gallon drink cooler over other shapes and sizes?

Another specific question is how shallow or deep of a grain bed is optimal?

___
I would just have to buy a new one for family cooler duties, since there's no way in h*** I'm letting SWMBO use my MLT for picnics.

 

[rklinck]

I've got a 5-gallon Rubbermaid drink cooler, and it works okay. Actually, I have to work to keep temps from rising during the mash.

You really need to mix the mash better. There is no way for the overall (average) temp of the mash to increase without adding energy. If your temps are rising, it is because your early measurements are from cold spots in the mash. You want to stir it up really good so that there are not cold spots.

As for other coolers, I use a 12.5 gallon rectangular cooler for my MLT. I am currently doing 10 gallon batches, so it is not a great comparison. But, even when I brewed 5 gallon batches, I got better efficiency from my 12.5 gallon MLT than from my 5 gallon drink cooler. I'm guessing this was a result of the difference in the build. I had a stainless coil for the 5 gallon MLT and a manifold in the 12.5 gallon MLT.

 

[kevo342]

I have the "Big Orange" drink cooler with the mesh tubing for filter for my MLT, and I consistently hit my target OG or occasionally hit higher than expected by a couple points. I have figured an efficiency of 68% and factor that into my grain bill calculations and it has worked really well for me. I can't however speak for other shapes as I have only used this one.

 

[schematix]

I use a 10G cylindrical cooler with a real false bottom (not mesh or tubing) and get about 90% efficiency. I would highly suggest going that route.

 

[billl]

Do you batch sparge or fly sparge?

If batch, it really doesn't matter. Use whatever is cheapest. Grain bed depth are meaningless stats for batch sparging.


If you fly sparge, a cooler that is taller than it is wide will make sparging a whole lot easier/efficient.

 

[BreezyBrew]

I bought the 40 qt marine cooler from igloo. Used it with a braid. Even with additional insulation in the top, I still lost 8 degrees during the mash. I even mashed thin.

I finally gave up, and went back to the drink cooler and braid that has a very tight top. I also insulated this. Now I only lose about 2 degrees.

 

[dracus]

I like my coleman 72qt Xtreeme cooler.

 

[BarefootFriar]

You really need to mix the mash better. There is no way for the overall (average) temp of the mash to increase without adding energy. If your temps are rising, it is because your early measurements are from cold spots in the mash. You want to stir it up really good so that there are not cold spots.

You're probably right, although I thought I had it covered. We poured the hot water from the pot into the cooler, and then as my faithful assistant slowly poured in the grain, I stirred it in to make sure it all got wet and didn't make dough balls. I then stirred it some more to make sure everything was nice and mixed up. When I figured out it was running too hot, I stirred yet more to try to cool it down. So I thought I had stirred it quite a lot -- certainly much more than normal (I previously put water onto grain rather than grain onto water, and I decided the grain onto water method is better). It's possible that my thermometer was off, but I doubt it.

 

[BarefootFriar]

Do you batch sparge or fly sparge?

If batch, it really doesn't matter. Use whatever is cheapest. Grain bed depth are meaningless stats for batch sparging.


If you fly sparge, a cooler that is taller than it is wide will make sparging a whole lot easier/efficient.

Fly sparge, mostly. Although honestly I don't really know why. I've read stats on both and it looks like for my batch sizes and so forth it really wouldn't make much difference.