Stalled Fermentation

[baltaperales]

I brewed a Düsseldorf Altbier on 1/17 and it's been fermenting at 62-63 deg temp. On day six the gravity reading was at 1.020. I raised the temp to 70 deg for a D-Rest on day 7. Today is day is 10 still at 70 deg and the reading is still at 1.020. Below is the recipe I used. Any thoughts.

Düsseldorf Altbier

INGREDIENTS
For 5.5 gallons (21 L)

2 cans (6.6 lb, or 3.0 kg) | Light Malt Extract

1.25 lb (0.57 kg) | Light Liquid Munich Malt Extract

0.5 lb (0.23 kg) | Special b Malt (120° L)

0.5 lb (0.23 kg) | CaraMunich Malt (60° L)

0.25 lb (0.11 kg) | Carafa Malt (400° L)

1.5 oz (43 g) | *Perle hops, 8.75% alpha acid (60 min)

1.0 oz (28 g) | *Tettnang Hops, 4.5% alpha acid (15 min)

0.75 tsp (3 g) | Irish moss (15 min)

1 package WLP036 Dusseldorf Alt Yeast

*Use similar hops, if Perle or Tettnag hops are unavailable.

SPECIFICATIONS

Original Gravity: 1.053
Final Gravity: 1.012
ABV: 5.4%
IBU: 42
SRM: n/a
Boil Time: 60 minutes
Efficiency: n/a
Pre-boil Volume: 3 gallons (11.4 L)
Pre-boil Gravity: n/a

DIRECTIONS

Steep the grains in 2 gallons (7.6 L) of cool water.

Heat the water to 170°F (77°C), then strain the grains.

Stir in malt extract and add enough water to bring the volume up to 3 gallons (11.4 L), and bring to a boil.

Add bittering hops and boil for 45 minutes, then add aroma hops and re-hydrated Irish moss and continue boiling for 15 minutes. Cool the wort, and then pour into fermenter with enough cold water to make 5.5 gallons (21 L).

Aerate and pitch yeast when temperature drops to 65°F (18°C).

Ferment at 65°-68° F (18°-20° C) for one week or until fermentation is complete. Age the beer in a secondary fermenter for one week at 65°F (18°C).

Carbonate to 1.5-2.5 volumes of CO2.

 

[Tiddy]

What did you have for an OG when you put it in primary? Did you happen to check?

 

[bigdaddybrew]

Swirl the fermenter to roust the yeast. Move it to warm dark spot and wait another week or two.

 

[heckler73]

62-63 is not 65-68.

http://www.whitelabs.com/yeast/wlp036-dusseldorf-alt-yeast

 

[baltaperales]

OG was at 1.054 and the LHBS recommended that I ferment at 62-63 deg so I took their advise. I had a very active fermentation for the first 3 1/2 days and then it started to slow down until I started the D-Rest.

 

[Damoxemus]

Swirl the fermenter to roust the yeast. Move it to warm dark spot and wait another week or two.

This. Did it before and it dropped a few more points.

Also, sometimes extracts don't drop ferment fully, fwiw.

 

[flars]

The stalling could be from under pitching the yeast, if the yeast was not fresh, or not enough aeration of the wort. Give the beer another week after gently stirring up the yeast and warming the wort to 68° to 70°.

 

[baltaperales]

I aerated the wort several times to make sure it got plenty of aeration, I'm going to try to gently swirl and see what happens. I understand that some extract brews don't always reach their target FG. Just think that 1.020 is a little high. At this point it's flavored water with hardly any alcohol content.