No. 2 gallons at boiling added to 3 gallons at 35F would only get you down to about 106F. You would need to cool the wort to around 120F before adding to the chilled water to get the final temp below 70F.brandonp22 said:If I have 2 gallons of wort boil and then add 3 gallons of fridge chilled water, will my temp fall easily enough in order to pitch?
HSA is a VERY overstated risk when it comes to homebrewing. It's POSSIBLE that HSA could cause long term stability problems, but I challenge you to find a homebrewer who can definitively nail down HSA as an issue with any of his brews. With the wort getting chilled almost immediately upon contacting the cold liquid, you really aren't creating HSA, anyway. HSA is most commonly encountered during the mash or during transfer to the boil kettle.2pugbrews said:I had a question something like this a while back. Someone warned against pouring hot wort into cold or icy water. Causes an undesirable phenomenon called "Hot Side Aeration" and suggested I do a search on that term. I did and decided not to do it.