Monday, 4 January 2010

Low fermentation temperature...brrrr

I checked on the AK this morning and found it bubbling away slowly but the temperature is a little low.  The little 25w vivarium heater stuck to the side of the FV is barely able to keep the fermenting beer above 17°C.  Originally I fitted two heaters but one melted.  I must get around to replacing it with a new one.  Anyway, currently it's at 17.2°C despite being set to 19°C.  This is OK and I would expect the fermentation to start creating its own heat soon but it's just a bit slower than I wanted.  Still, it should make a nice, clean beer and stop the 1.75kg of sugar causing nasty flavours.


  1. I am having the same problem with my conical. The temperature is around 16-17C despite the controller being set to 20C. I did notice that during the vigourous phase of fermentation the temperature was 1.5-2C higher (due to the heat produced by the yeast, I guess). I need better insulation I think.

  2. Insulation is the key at this time of year. The vivarium heaters are great but it's asking rather a lot of one to maintain 55l of beer at 18C in sub zero ambient temperatures.