US-05 stalling out

[wlssox524]

I've got an amber ale that's been in primary for 3 weeks and seems to be stuck at 1.020. I had it in a ferm chamber set to 66F and I believe it stayed there for a few days but my basement then dropped to around 60F. The yeast was rehydrated, OG was1.060, and the wort was oxygenated with pure O2 so I don't think there are any other suspects for stopping at 1.020. Obviously 60F is in the range for us-05 but could a drop of a few degrees have put the yeast to sleep?

Regardless, would love input on my best options: I already brought the bucket to a 68F room and roused it slightly. Should I wait to see if that does the trick (it's been 3 weeks since pitching)? I also have a spare sachet of us-05--is it worth pitching some or all of that to help out?

Thanks!

 

[Yooper]

It sounds done, and repitching won't help. It sounds like there are some unfermentables left in there, from crystal malt or extract or a high mash temperature.

 

[wlssox524]

It sounds done, and repitching won't help. It sounds like there are some unfermentables left in there, from crystal malt or extract or a high mash temperature.

You could be right, but that would be low ~65% attenuation and I only had a pound of c40 (rest of the recipe was 1# carapils 9.5 # two row and 4 oz chocolate malt. Mash temp was 154 ..seems a little high to finish there no?

 

[Dirty25]

Us-05 will keep chugging away at low temps, it don't care. 1lbs or cara pils and 1 lbs of crystal would leave a ton of residual sweetness

 

[wlssox524]

Us-05 will keep chugging away at low temps, it don't care. 1lbs or cara pils and 1 lbs of crystal would leave a ton of residual sweetness

Recipe is here and says expected fg is 1.014. http://restorationbrewing.blogspot.com/2010/07/tasty-american-amber.html?m=1

 

[Yooper]

Recipe is here and says expected fg is 1.014. http://restorationbrewing.blogspot.com/2010/07/tasty-american-amber.html?m=1

With 17% crystal malt (carapils is a crystal malt), and a mash temp of 154, it is done at 1.020.

 

[boydster]

Agreed. 3 weeks in primary and loads of unfermentable sugars, it's done.