Last year I upgraded to a Coleman Extreme 70qt for my batch-sparge setup.
This cooler will keep stuff frozen for days on end. However at mash temps it loses about up to 5 degrees over 90 minutes. I noticed this after the initial couple of batches and attributed it to thermal absorption even though I pre-heat my tun.
Now I’m not so sure. Maybe I’m losing some heat around the lid somehow? Anyone got any ideas?
Hi euge,
I have the same cooler and rarely lose 2 degrees in 90 minutes. Couple thoughts. Make sure you stir up the mash thoroughly. Cover the cooler with towels, blanket, sleeping bag or something to help insulate it. Don’t open it again until you’re pouring the vorlouf back in. Maybe others will have more ideas…
+1 on covering it with towls. I had a heat loss problem during the winter months until I used the towls.
+1 on towels, etc.
Another guy I talk with has fitted the inside of the cooler with some solid styrofoam to increase the insulation. I worry about that becoming another source for mold/etc.
My Cube 60Qt held to about 1 degree on a 90 minute mash in 30 degree weather, I am good with that.
I forgot to ask-Is the cooler blue? Red and Silver coolers are inferrior.
You’ve learned well, Slim!
I’ll probably look at the lid. Bet it isn’t insulated. Blankets or towels hmmm…
Thanks guys.
damn… i just got two new red rubbermaid coolers… really they are orange… can i make good beer in an orange rubbermaid?
Nope, you should just mail them to me, & buy yourself new blue ones ;D
I’m not sure about the cooler you have, but many coolers have no insulation in the lid. This is easily addressed by drilling a few small holes in the lid and filling it with expanding foam insulation from a can. It’s sold under the brand name “Great Stuff.” I used it to fill the lid of my 60-qt Igloo, and it helped. I still cover & wrap the mash tun with a couple blankets when the weather is cold, though. I’m brewing outside tomorrow, and the forecast is for a high of 22F.
That is a real good point. I’m pretty sure my Ice Cube Lid is just relying on “dead air” and is hollow too.
I think the weekend is not looking good for brewing now…
Folks, I’m afraid to tell you that you are delusional if you think the red or blue or purple or any color cooler for that matter has anything to do with the thermal capability of a given cooler. :-\
But it’s the group power of positive thinking that actually allows for the increased thermal capacity of the blue cooler. ;D
I am doomed in my better beer quest.
I have an orange cooler 
Part of what makes the Xtreme line of coolers “Xtreme” is insulation in the lid so that’s probably not it. Although additional insulation in the form of blankets/towels certainly won’t hurt.
I’m sure the lid is insulated. When I uncover mine the outside surface of the lid is room temp. If it wasn’t insulated I’m sure it would be much warmer…
The lid got hefted and inspected short of drilling any holes. Pretty light. There might be some insulation since it has a nice thok. It’s constructed of thick poly.
The mash experience is otherwise good with it. I’ll try some blankys.