Chilling cool, pitching warm - advice?

[MaskdBagel]

I'm using 3724 for a batch this weekend, and I'm wondering the best way to go about it.

Pertinent info:

1. I use a plate chiller, my ground water is ~45 degrees, and I don't have good flow control on the cold side.

2. 3724 likes it WARM, so I would ideally like to pitch at 88 degrees.

3. Agitation or aeration coming out of my chiller hose are currently my only good methods to oxygenate.

4. Target OG is 1.075, so good oxygen will be important to get things started.

If I could chill to exactly 88, I'd just put a spray aerator on the end of my "wort out" hose, get it all nice and foamy, and pitch right away. However, I know I can't. It'll probably be something closer to 55 coming out of the chiller.

Two options, as I see it. First is to aerate as well as I can into the fermenter, pitch at 55, and set my fermentation chamber to get to 88 ASAP - would probably take 10-12 hours. Second option is to go from the chiller into the fermenter at 55, warm to 88, and then try to agitate as well as possible before pitching.

You don't use 3724 because it's neutral (obviously), so I'm wondering if the first hours are crucial enough that I'm going to sacrifice some of that character by pitching cold. On the other hand, I'm unlikely to get as much oxygen dissolved by shaking the fermenter 12 hours after chilling.

What would you do in this situation? Any other options come to mind?

 

[Aaron Beers]

I'm not following why you can't control the flow rate of your chill water and your wort... A simple ball valve on the chill water is all you'd need.

In any case, if your wort is coming out colder than you want to pitch at, then, simply, don't chill all your wort.

If you have wort coming out of the kettle at 200F, and coming out of the chiller at 55F, and want to pitch at 88F, then you need to increase the temp of the 55F wort by 33F and decrease the temp of the 200F wort by 112F.

Let X be the gallons of 55F wort and Y be the gallons of 200F wort.

X+Y=10
(X*33) - (Y*112) = 0
X*33 = Y*112
X=10-Y
(10-Y)*33 = Y*112
330 - 33Y = 112Y
330 = 145Y
Y = 330/145
Y = 2.27 gallons
X = 10-Y
X = 7.73 gallons

So use 7.73 gallons of the chilled wort and add 2.27 gallons of the hot wort to have 10 gallons of wort at your desired temperature.

Or, use a ball valve on the cold water in the plate chiller, and preferrably a second valve for the wort throught he plate chiller.

 

[MaskdBagel]

I'm not following why you can't control the flow rate of your chill water and your wort... A simple ball valve on the chill water is all you'd need.

In any case, if your wort is coming out colder than you want to pitch at, then, simply, don't chill all your wort.

If you have wort coming out of the kettle at 200F, and coming out of the chiller at 55F, and want to pitch at 88F, then you need to increase the temp of the 55F wort by 33F and decrease the temp of the 200F wort by 112F.

Let X be the gallons of 55F wort and Y be the gallons of 200F wort.

X+Y=10
(X*33) - (Y*112) = 0
X*33 = Y*112
X=10-Y
(10-Y)*33 = Y*112
330 - 33Y = 112Y
330 = 145Y
Y = 330/145
Y = 2.27 gallons
X = 10-Y
X = 7.73 gallons

So use 7.73 gallons of the chilled wort and add 2.27 gallons of the hot wort to have 10 gallons of wort at your desired temperature.

Or, use a ball valve on the cold water in the plate chiller, and preferrably a second valve for the wort throught he plate chiller.

I think this will be the way to go, yeah. I appreciate the math! Saves me some time. In this way, hopefully I'll hit close enough (55 being a fairly close estimate) that I can just pitch and set the temp at the same time and not have too much time to get to 88. Certainly better than starting it all at 55! Really appreciate the input here. Come by for one on me if you're around Seattle at any point.