I have a ceramic reptile bulb heater. When cleaning the 1/4 inch of beer on the bottom and splatter on the sides the dangling thermometer was in the way so I moved it on the ledge. One of the fermenters I see some bubbles so I guess that's a good sign. My question is what temp would kill the yeast?
I made a stout about 15 years ago before I had any idea of what I was doing. It was summer and it fermented in the 80's maybe peaking at 90F. When it was finished it had a strong odor like nail polish remover. I still have some of this beer - it hasn't changed a bit.
Let this be a lesson! I unplugged the freezer since it's almost winter. Stupid stupid!
I also knew that after seeing this ceramic heater in action that 150 watts was WAY to much. I am tossing it out for the lowest possible watt ceramic heater. I guess I will wait the two week primary and then taste it before I put in glass carboy.
I use a similar setup to you....your issue was that you forget to put the sensor back in freezer....if you had done that the heater would have shut off and everything would be fine.
I use a 200 watt My Buddy Heater (something like that)...with no issues
The one thing I did learn on my first batch I fermented in this setup is that (even in the winter, with my freezer in garage) ....the self heating that the yeasties do during peak fermentation will heat up the freezer since the extra heat cannot escape...so now I simply keep the lid cracked about 3/4" with a small block of wood for the first 3 days or so of fermentation. after that I close it
EVERYONE is entitled to my opinion!
Primary #1: Irish Red
Primary #2: Empty
Primary #3: Empty
Bee Cave Hefeweizen