Help me understand efficiency

[petep1980]

I just finished sparging and I collected 7.5 gallons total and it reads 1.053 on my refractometer @ 150°F. If you temp adjust that comes out to 1.072 going into the kettle from ~16# of grain.

Somehow that comes out to a 97% efficiency.

Where is my error?

 

[Killervector]

Refractometers usually correct for temp. I'm guessing if you do it again with it cool, you'll still get 1.053.

Mine says ATC on it... which I'm 90% sure means Automatic Temperature Correction.

If you go with 1.053 I show you'd be around 69%... doing the rough math.

 

[petep1980]

Refractometers usually correct for temp. I'm guessing if you do it again with it cool, you'll still get 1.053.

Mine says ATC on it... which I'm 90% sure means Automatic Temperature Correction.

If you go with 1.053 I show you'd be around 69%... doing the rough math.

I do have the ATC one. Thanks. I figured that was it. I am usually at 75% with two sparges, I dropped one of them.

 

[petep1980]

So now I figure with a 90 min boil I'll end up around 1.062 and I wanted close to 1.070. I wonder if I should add some sugar.....

 

[ajf]

If you boil down to 5.67g you should end up with about 1.070
(53 * 7.5 / 5.67 = 70), and that sounds reasonable for a 90 minute boil.

-a.

 

[petep1980]

I am going to add the sugar. The recipe does actually call for it. This way I can avoid a 90 minute boil.