New2HomeBrew said:
I see that you add an additional water volume before recirculating. However it says nothing about water temperature. Should this initial addition of hot water be at the mashing temp or should I use the temperature calculations from John Palmers book for the fly sparging technique? I believe I read somewhere that the sparge water temp should not go over 170 to prevent extracting tannins.
Did you see this thread from a few days ago?
https://www.homebrewtalk.com/showthread.php?t=35416
It discusses the number of batches used when batch sparging.
Once the mash is complete, any water additions should designed to raise the temperature to sparge temperature (165 - 170 degrees).
I usually fly sparge, and when fly sparging, I heat my sparge water to 185 degrees. I also mash out to raise the mash temperature up to about 168.
When I add my 185 degree sparge water to my unheated HLT, the temperature drops nearly 10 degrees. By the time it has meandered through the tubing to the sparge arm, it has cooled to about 170. I don't keep the water below 170, but do keep the sparge below 170.
Also, the 170 isn't a switch. You will extract tannins when sparging. It is unavoidable. Hotter water extracts more tannins, but providing the temperature is kept below 170, and the pH of the sparge is kept below a value that I don't know, you will not get excessive tannin extraction. The normal way to control this is to keep the sparge temperature at or below 170 and the gravity of the runnings at or above ~1.010
New2HomeBrew said:
I am assuming that I will loose roughly the same ammount of water from my one hour boil for a 10 gallon batch as I will for a 5 gallon batch. I have had to bring my initial boil volume up to 7 gallons for a 5 gallon batch loosing close to two gallons during the one hour boil. Do you think that this is a correct assumption?
Don't have a clue. I've never brewed 10g batches
New2HomeBrew said:
I also tried plugging in my recipe details to the spreadsheet listed on that batch sparge webpage. The first run gravity was over 1.4 and the second was listed as .4. Am I doing somehting wrong? It states on that webpage that the gravity should never drop below 1.019?
I think you have done something wrong (or the spreadsheet is wrong).
I don't care how much sugar you dissolve in your sparge, you cannot get a gravity of either 1.4 or 0.4
-a.