I'm getting ready to start all grain in the next few weeks, as college is more important(according to my parents) I've had to put off brewing for a while. I have everything sourced including a 60 litre cooler that I got for €30 in home store and more. My question is, is a 60L cooler too big for only doing ~21L of beer. Will the bigger amount of headspace cause me problems with holding mash temps and I think their is a lot of deadspace as the tap is about 40mm above the bottom surface. Should I look around for a new cooler, or carry on with it?
I think it's a bit big for your needs DC.
I used a 32l Cooler for ~23l batches.
I've 50l mashtun for 20l batches. I had a 28L before and I struggled. Plus with a big MLT if times a factor you can try no spare brewing. I say for that price you've done brilliantly.
I've the same cooler and brew 20l batches. I wrapped the whole thing in that insulating foil you get in Aldi and I couldn't get over how well it holds temp, doesn't drop at all. Enjoy!
If you want to do high gravity beers such as Russian imperial stout or a barley wine your going to need a lot of that extra volume as they will require around 10kg of grain. I would add some additional external insulation to it and also get a block of aero board. Get a sheet of tin foil & place it on the top of your grain bed after mash in. Have your aero board cut to the size of some of the void for your average beer & this can help insulate the top of the mash.
Shanna