I'll be making my first partial mash this upcoming weekend, have a new 8-gallon mega-pot, and would like to take advantage of finally being able to do a full boil. Since I'll be doing this on a stove top that takes forever, I'm concerned about lag time after sparging, topping off the pot with another 4.5 gallons, and getting the volume up to a boil.
Would it be ok, at some point while the mash is resting for the hour, to simultaneously get the additional 4.5 gallons to a boil, or at least warmed up to my sparge temperature? I just feel like something weird will happen post-sparge by 'cooking' everything for so long before ever getting up to a boil before I add the rest of the fermentables. Any thoughts would be greatly appreciated.