RichBrewer

Recipes 

For the longest time I had problems getting my mash to the proper temperature in my rubbermaid cooler. I would add the strike water and hit the temp right on the money only to have the temp drop below 150 degrees. I tried pre-heating the cooler and that helped but it still dropped too much. This last batch I figured it out. The cooler absorbs heat from the water. Heres what to do:

Pre heat the Mash tun with hot water. Then heat your strike water to about 5 degrees hotter than your target temp. Pour the water into the tun and let it cool down to your strike temp then add your grains.
I did a 90 minute mash this way and I only had a 2 degree drop from 154 degrees.

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Cheers,
Rich

Mikey

Recipes 

An easier way is simply observe how many degrees you lose because of using a room temp mash tun, and next time increase your strike water temp by the same number of degrees.

Promash has a utility to help calculate this, you just need to figure out what the thermal mass of your tun is.

Baron von BeeGee

Recipes 

Sounds like your cooler isn't insulated that well? I use a Coleman Extreme and it doesn't typically drop more than 1-2F over 60m even at 50F ambient.