Yeast slow to start.

[Bobstrolz]

Made my first all-grain brew on Sunday and pitched yeast (Wyeast Ringwood ale) when wort had cooled to 21 degrees. Temperature since then has been 20-21 degrees and after 36 hours there doesn't seem to be much activity. How long do I leave it before panicking and adding more yeast? Maybe a different type?
Thanks.

 

[johnnyboy1965]

Did you make a starter?

 

[simon12]

I do AG brews on Sunday and most are fermenting like mad 1st thing on Monday but a few didn't get going until late Tuesday and its not make a difference in the finished beer.

 

[Bobstrolz]

I didn't use a starter. It was one of those slap-pack things.
I made a malt extract recipe 3 weeks ago using dried yeast and fermentation was vigorous after 12 hours and I was just expecting the same from this all-grain/wyeast brew.

 

[Bobstrolz]

Panic over. Came in from work and there's a nice, healthy looking froth sitting on top of the brew, 48 hours after pitching the yeast.