[crustybfv]

So, doing an extract demo tomorrow.  Planning on 2.5-gallon boil, and adding 2.5 gallons after whirlpool to drop the temp.  (I'll be brewing outside without my usual access to sink full of icewater-my normal stovetop/chill method).  What temp should the liquor addition be to drop my temp down to 140 or so (the upper limiy on my fermenter)?

[Vin S]

You can always sub 1gallon with an 8lb bag of ice. It will get you closer to the 140 temp.

[kramerog]

68 F.

[santoch]

I would be leery of adding ice to achieve temps below pasteurization level.  Bagged ice may not be as sanitary as we need for brewing.  It's playing Russian Roulette with contamination issues.  While I have heard of many batches where it's worked ok, I have also seen it backfire.

HTH-

[a10t2]

So, doing an extract demo tomorrow.  Planning on 2.5-gallon boil, and adding 2.5 gallons after whirlpool to drop the temp.  (I'll be brewing outside without my usual access to sink full of icewater-my normal stovetop/chill method).  What temp should the liquor addition be to drop my temp down to 140 or so (the upper limiy on my fermenter)?

To a reasonable approximation:

2.5*T_w + 2.5*T = 5*140 -> T_w + T = 280 -> T = 280 - T_w

where T_w is the temperature of the wort after whirlpooling. This is an approximation because the specific heats of water and wort aren't quite the same, but you'll be within a few degrees.

Or 68°F if the wort is at 212°F, but it won't be after whirlpooling.

Edit: I'm not sure why you'd chill the wort to just 140°F though. Instead I freeze the (boiled, sanitary) water and come out with wort at ~60°F.

[scarecrow]

I normally just have a steel tub filled with water from the hose and dump in some ice. drop my wort into the ice water and watch the temp drop with a quickness. Once I'm down to 120 I transfer to the carboy that already has my 2.5 gal of water waiting. works pretty good so far for me without any problems.