Originally Posted by tuskenraider
I've found using about 190° sparge water gets me between 166-170° with 11-14 lbs. of grain in my 10 gal. Igloo cooler. As mentioned previously, you don't have to be that precise, but close is nice I suppose.
Thanks for all the responses. I learned things from many of them, and this is pretty much the exact answer I had hoped for.
One thing that I didn't mention that does play into all this is that I don't always boil right after mashing. On occasion I'll store the wort overnight in a sealed bucket and in a fridge because I don't always have the 7 hours to commit to a brew session in one block of time. So getting the bed to 170 takes on a bit more importance for me in those situations.
Like on Sunday. I mashed, went to a piano recital, then came home and boiled. :-)