First AG E-HERMS brew day, 0.034 off on the OG, what did I do wrong?

[azwillnj]

I just brewed my first batch on my new E-HERMS system comprised of 3 kegs. I did a 5gal batch based on OhioDad's Dragon's Milk recipe. Followed everything to the degree and minute but for whatever reason I was off on my OG by 0.034 points.

It was an E-HERMS system and I was recirculating for 65 mins of the mash. The last 10 mins I stopped to ramp the HLT to 168F for the sparage.


Here is the recipe:

13 lbs Pale Ale Malt 2-Row (Briess) (3.5 SRM)
1.5 lbs Munich Malt (9.0 SRM)
1 lbs Caramel/Crystal Malt -120L (120.0 SRM)
1 lbs Chocolate (Briess) (350.0 SRM)
4.0 oz White Wheat Malt (2.4 SRM)

Mash in 6.25 gal at 162F
Mash for 75 mins at 150F
Sparage at 168F to get total pre boil vol of 7.25 gal

Estimated OG: 1.088
Actual OG: 1.054

I forgot to take the Pre-Boil SG.. rookie mistake.

What went wrong?

Alex.

 

[helibrewer]

Hard to say without knowing your first runnings SG.

What mash ratio did you use? Did you batch or fly sparge?

Are your thermometers correct, are your volumes correct?

 

[azwillnj]

I used the mash ratio that BeerSmith told me to use, haha.

The thermometers are correct, verified with ice water. The volumes are also correct, verified with a (giant) measuring cup.

I was continuously recirculating through the HERMS coil for about 95% of the mash.

First runnings SG? What data points should I be collecting during the sparage?

 

[LBussy]

Are you sure you got doughed-in well? That sounds like a third of your grain did nothing.

 

[azwillnj]

Yeah, I stirred it for a long while.. twice in fact. The only thing I can think of is that I may have rinsed the grain too much. I was unclear about how to sparage with the clean water.. Should I completely drain the mash tun, then add some water?

 

[azwillnj]

Could it be something with the PH? or should I have mashed for longer even though BeerSmith calculated it would be fine?