I've got no fermentation going 24 hours after brewing. Normally I use smack packs but this batch was a white labs vial. I also normally use a starter but this time due to time restraints did not. The foam that was formed from aeration (shaking the hell out of the carboy) is still on top of the wort, but there is no fermentation activity.

Should I wait or re-pitch another vial which I luckily have?

First check the temperture of the wort in the carboy to see if it is warm enought for fermentation to start. If it is within range for the yeast you are using then I would wait atleast 48 hours before pitching another vial of yeast.

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The Czar

A safe way to check the temperature of your fermentation is to put your thermometer in a glass of water next to you carboy. Fill the glass with water that you measure to be close to the room temperature. Wait an hour or so see what your temp is.

I bow to thee...

42 hours and signs of fermentation started...

At 52 hours it is nearly a healthy fermentation, who would have known...

But, I'll be sure to always use a starter regardless of the time situation!

Always use a starter!

Brewing much like life is an on going learning process.

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The Czar

To me the funny thing is that I ALWAYS use a starter, this was the one I didn't. But it's fermenting like mad now, and tomorrow I'm going to rack it and pitch a huge pale on on top of the cake so it should be good and healthy still so I bet I'm fermenting in an hour after brewing