Stuck at 1.024?

[BrookdaleBrew]

Brewed a brown ale recipe I came up with about 3 weeks ago. The grain bill is below. I mashed at 154. Took a gravity reading about a week after pitching and it was at 1.024. Took another reading today, 2 weeks later and I'm still at 1.024. OG was 1.066. Yeast is washed US-05.

12.00 lb Pale Malt (2 Row) US (2.0 SRM) Grain 88.89 %
1.00 lb Special B Malt (180.0 SRM) Grain 7.41 %
0.25 lb Crystal 150 (150.0 SRM) Grain 1.85 %
0.25 lb Pale Chocolate Malt (200.0 SRM) Grain 1.85 %

I just find it hard to believe a recipe with almost 90% 2 Row is going to finish that high. Obviously all the dark specialty malts left some unfermentable sugars, but it still seems way high. I'm attempting to raise the wort temp from 64F to around 70F to see if that makes a difference.

 

[barrog]

Someone correct me if I'm wrong but given the amount of specialty malts and your mash temp that sounds about right.

 

[BrookdaleBrew]

Eh, if anything I think it's the fact that the specialty malts are so dark. I brewed another beer around the same time with similar percentages, same mash temp and an OG that was 13 points higher. It finished at 1.014.

 

[theonetrueruss]

I doubt it's the specialty malt.. I mashed at 154 for a brew a while back that started at 1.9OG and finished 1.025 and it had about 25% crystal/chocolate malt plus a lb of lactose. (it was a sweet chocolate milk stout). Of course my yeast was different so maybe that matters... maybe there was a lack of oxygen/nutrients etc?

Any chance the thermometer is measuring badly and the mash temp was actually a bit higher?

 

[BrookdaleBrew]

I don't think it was an oxygen issue as the batch that fully attenuated and the stuck batch were aerated the same way. I pour from the kettle into a bucket through a strainer. I did use a different yeast. Fully attenuated batch got fresh notty and the stuck batch got washed US-05. So maybe the yeast just crapped out on me. I think it was 3rd generation yeast.

Could I add yeast nutrient to the fermentor at this point or would that not do any good? I could also add a bit of corn sugar to dry it out and maybe get the yeast going again.

The sample tasted fine though, so I may just bottle it as it is.

Oh and I have already tested my hydrometer to make sure it's accurate. I'll test the thermometer as well.

Thanks for the suggestions!

 

[dave5155]

have you tried swirling the fermenter to get the yeast back in suspension? That final gravity does seem very high to me as well. That really isn't alot of specialty malts like you said. I'd try warming it up and swirling it.