Do coolers wear out?

[jwalker1140]

I've brewed three partial mash batches using a 4-gallon Coleman cooler, the rectangle kind, and each time my temp has dropped ~4 degrees by the end of the 60-minute mash.

The cooler is about 20 years old, which makes me wonder if there is insulation in them that can wear out over time (I hope this isn't as dumb of a question as it seems to me as I type it). I've heard they can crack but I haven't heard if they can simply lose their insulating ability.

I suspect my temp drop has more to do with the 1-1.5 gallons of head space or the fact that I haven't preheated the cooler but I thought I'd ask.

 

[ron,ar]

I had one in which the insulation disenigrated and fell down inside the walls. It didn't leak, but didn't hold temps as well as it used to.

 

[theveganbrewer]

Well, I guess the easiest solution is to buy a new cooler. You got 20 years out of this one, you've gotten your money's worth .

I don't think the insulation would be going bad, unless it'd gotten wet somehow. You could try preheating, wrapping in foil, and covering with a fleece blanket or jacket during the mash.

 

[Stauffbier]

Yes they do wear out. The repeated high temps can de-form and warp them after many repeated uses. The insulation can also break down, as well. Some last longer than others. If the lid doesn't close right, or temps won't hold (like in your case) it's time for a new one! Make the old one a bottle conditioning container..

 

[wilserbrewer]

Try preheating the cooler! Just simply "overheat" your strike water and let it cool to the actual strike temp. I would not buy a cooler just to a "new" one. I doubt the age of your cooler is the issue. Also, give the mash a good five minutes for the temp to stabilize before you take a mash temp reading...some check temperature too soon and interpret a temp drop, when this is actually just the mash coming to a stable temperature.

 

[jwalker1140]

Guys, thanks so much for all the information. I may start by overheating my strike water, as wilserbrewer suggests. The lid is still tight, and other than a puncture in the side from when a bear took it from our campsite one night, it's in good shape. (And no, I didn't chase after the bear, I waited until morning to recover it after the bear had finished eating our hotdogs and eggs.) I may also shoot some insulation into the lid and sides or wrap it in some fleece as theveganbrewer suggests. Thanks again!

 

[wilserbrewer]

I may also shoot some insulation into the lid and sides or wrap it in some fleece as theveganbrewer suggests. Thanks again!

Just use a little care w/ that spray foam...I have heard that sometimes it doesn't set properly if it is sealed within the lid...and it is also some of the stickiest messiest stuff on the earth, and it is not cheap to begin with...this being said, IMO don't bother.

 

[CPFITNESS]

i heat up an 1/2 to gallon of strike water and throw it in there and swish it around a bit then dump it out. I don't simply heat to higher temp because i add water and grains a bit at a time, I don't just dump grain in on top of the water. I'm no pro but I get the sense that some people take hitting specific temps a bit too seriously. I have a book and it talks about keeping the mash in a range of 144-152. thats a pretty big range. I've found I have to be careful that I don't start getting higher temperature readings in the tun from leaving the lid closed on the cooler.

 

[gkeusch]

My rectangular Igloo cooler lasted about 10 or 12 brews and I only lost a few degrees during the mash, but then about a quarter of the bottom buldged up (maybe a half-inch or so), and the next time I used it I lost about six degrees.
I usally put my hot liquor into it at a pre-strike temp of 170F or so, (sometimes a few degrees more) prior to mashing in.
I'm not very happy that it only lasted that long. Thinking about going back to a canning pot in an insulated box.