What is your SG: of your batch sparge

[mdd134]

Have you ever tested the runnings of your batch sparge, not the mash SG: but the last sparge going in to the kettle? I have been checking mine the past 2 brews one was a single sparge one was a double and the SG: seems to be 1.020 even on a double batch sparge. which seems that is a lot of sugar left behind.

I did cool it first so it should be correct.

[Lerxst]

Sweating your Eff%?

fwiw, here is a temp correction chart:
http://hbd.org/brewery/library/HydromCorr0992.html

[Ó Flannagáin]

You have to realize that a lot of sugars are going to be left when you double sparge. It's all about the total amount of sparge water used... althought test have shown double sparging will up your efficiency a bit, but not a bunch.

[Evan!]

I don't test my runnings...don't think I ever would, unless I were to change the way I brew entirely. The way I do things, I set up all my sparge and strike volumes based on my typical evap rate, with grain absorption and dead space all accounted for, in order to end up with 5.5 gallons in the fermenter.

Some people, I would surmise, approach it from the other direction: they fly sparge and then just stop their runnings when the runnings reach a certain SG. This is problematic to me because, while it might give you great efficiency, you also have to adjust your boil time (or actually add water) "on the fly" depending on what your preboil volume ends up being. I don't buy this approach, so, my runnings end up wherever they end up.

The only thing I sometimes do is take a reading of my total wort in between the mash and boil. If it's high or low from what my preboil SG should be, it's much easier to adjust the recipe at that point (prior to adding bittering hops) than it is at the end.

What is your efficiency, typically?

[MrMarbleHead]

Never really checked the final runnings from my tun. But like Flanny & Evan! said, it is all about getting your volumes right. If you can nail that down, then move on to the next possible cause. But just change one thing at a time, that way you know exactly what is causeing it.

I posted in your other thread about a manifold that may be the next step if you have exahsted all the other possiblities.

Oh and one thing i can say as a general guide line from what i have read is that you don't want to go below a 1.010 gravity on your runnings fron the tun, you risk the extraction of tanins at that point that can lead to astringency.

[DrunkenSatyr]

I checked last time with a triple sparge (YEAH i KNOW A BIT OBSESSIVE) They were 1.010