Fermentation Question

I made the first batch with my new all grain set-up on Saturday (an oatmeal stout). I made the mistake of letting the water run on the immersion chiller while we went inside for dinner, and over-did the cooling. Then I compounded it by pitching the yeast anyway, rather than waiting for the wort to return to room temperature. I did not check the actual temp, but it was plenty cold. There was still very little noticable activity when I went to bed six hours later. The next morning, there was none. I do have what appears to be settled yeast in the bottom of the carboy, but the airlock never moves. I'm wondering if the visible fermentaion was fine, and I just missed it, or if it never happened at all. What should I do now?? Re-pitch with fresh yeast??? Wait???

Any advice will be appreciated.

Usually yeast is stored in the refrigerator, so you aren't going to damage it by putting it in cold wort. It will probably just be dormant until it reaches a warmer temperature. Cold wort causes the yeast to flocculate, which would explain why yours has settled so much.

I would try swirling it around to get the yeast back into solution, once it is at room temperature, assuming you haven't already done so. Based on your description it sounds like it hasn't been even 24 hours yet - dry yeast (which I assume you used) is usually pretty quick to start, but I don't think you need to worry just yet - especially since the yeast has spent quite a bit of that time colder than it wants to be.

You can start by resuspending the yeast.

Yeast, like any suspended particulate, will drop out of cold wort. By the time it came back up to room temperature the yeast was probably already settled on the bottom.

Give the primary a good shake, resuspend the yeast and hopefully kick off the fermentation.

If all else fails, pitch more yeast after 48 hours of inactivity.

RAHAHB!

Don't open it, just give it a shake and you should have activity in 48 hours depending on what kind of yeast you used, and how you prepared it.