Viable Yeast Temps

[Ebonheart]

I'm in the fourth week of fermentation on my first ever batches of Baco and DeChaunac, third week in carboys after a week in buckets. We've suddenly gotten a blast cold cold air in the Northeast. We're keeping the carboys in our wine room, a room 3/4 underground and averages around 60. We have a plan for another room with higher temp, but I'm still a few IKEA trips away from getting it set up. Given temps this week (30-40s outside). I've been trying to keep the wine room between 60 and 65 consistently.

My understanding is that 60-65 should be ok, and, in fact the DeChaunac is still pretty consistently perking the airlock. At what temperature should I be worried about killing of the yeast, and is that possible at temps above freezing?

 

[jamesngalveston]

below freezing will not kill yeast, it will go dormant only.

 

[salcoco]

I would just put a electric blanket with another covering it to keep wine warm. yeast will stop fermenting at about 45? and stay dormant until heat rises. but you risk yeast stress which will yield off odors. Keep yeast healthy with nutrients and keep temp at 60 or better.