Mash tun size

[food00d]

I am gathering materials to make my first AG batch, and have a question about mash tun size.

I was given a 120qt rectangular cooler, and am wondering if I would be able to use it for 5gal batches - or is it way too big? I have read some information about people using coolers this size for up to 23gal batches, just wondering if I would be able to do a smaller batch or if I'd lose too much heat because of all the headspace in the cooler.

If I can use it however, I would like to. The price was certainly right.

 

[TVarmy]

You should be fine. Just preheat it with hot water first. I used hot water from the tap for preheating in my mash.

 

[Zen_Brew]

You may be pushing the envelope to far with that cooler. The only issue is not heat loss, although that can be an issue as well. Putting a 5 gallon grain bill in such a large cooler will spread your grain out pretty thin. A certain depth of grain is useful as when you drain the cooler the grain bed acts as a filter. The more grain your wort has to run through the better the filtering. A deep grain bed also ensures during vorlauf that as you pour wort back in you are not disturbing the bed deep enough to disrupt the filter bed that has formed.

Another issue will be your dead space in the cooler. There is always going to be a certain amount of unrecoverable wort beneath your drain level. As the surface area of your cooler increases the volume of unrecoverable wort increases also. This will hit your efficiency as you have to account for all the sugars lost to your dead space volume. Once you understand the loss you can account for it with larger water volumes and increasing the size of the grain bill.

It may work, but it will be sloppy. You will likely lose a lot of efficiency and heat, and you will have questionable filter bed efficiency as well. I'd say 10 gallons is the smallest size I would want to do in a cooler that size, and most would opt for a 60 qt at 10 gallon batch sizes.

 

[Pubwilson]

Yah! Look at it this way, you should make more beer!

 

[MikeG]

Wouldn't hurt to insulate at least the top, possibly use a blanket to prevent heat loss. Good luck.

 

[food00d]

Thanks for the responses.

Looks like it's time to start looking for a deal on a cooler. 60qt would be optimal size for 5-10gal? Or would 48 do better? I don't anticipate doing 10gal batches for quite some time.

 

[ICanHazBeer]

I purchased a 70qt Coleman Xtreme from Walmart.com for 35-36 bucks, shipped, about 4 weeks ago. Check there. Lots of people on here have made them from that cooler, that is why I chose that particular model.

 

[shortyjacobs]

I have a 60 qt, and it works fine for 5 gal batches, but really shines for 10 gal batches. If I were only to do 5 gal batches, I might instead have gone with a 48 qt. The 5 gal batches in the 60 qt still only lose 1-2 deg/hr, (spray foam into the lid to help insulate!), but the grainbed is a bit thin for my liking on lower OG beers.

 

[MikeG]

Thanks for the responses.

Looks like it's time to start looking for a deal on a cooler. 60qt would be optimal size for 5-10gal? Or would 48 do better? I don't anticipate doing 10gal batches for quite some time.

https://www.homebrewtalk.com/f11/how-big-your-mash-tun-needs-123585/

 

[food00d]

Fantastic. Thanks.