I was mashing away 10 gallons of Centennial Blonde. After doughing in, my temp was 148 instead of 150. So I took my trusty heat stick and used it to increase the temp to 150 or so. Took a lot longer than I thought, though.
I stirred a bit, then let it mash away. After about half an hour I noticed the temp had risen to 152. I decide to release a bit of heat by stirring.
Well, hot damn, as I stirred the temp soared almost to 160. I used some ice and stirring to bring it back down. It was at 144 before I knew it and I had to use the heat stick again.
I'm wondering if my thermometer is malfunctioning or if I need to do a better job stirring. Things is, I try to be cautious of bumping the thermometer stem too much. It's mounted thru a drilled stopper and I once bumped it and it began leaking and I had to stop and get it seated right again.
So what do you think? Hot spots? Poor stirring? Faulty thermometer?
Can anyone recommend a digital thermometer to me? When I'm trying to really dial in the temp the dial thermometer makes it rough on my eyes.
Hope the beer turns out!