Chilled Wort mysteriously reheating?

Yesterday I brewed and chilled down to 80F (according to calibrated boil kettle thermometer) with an immersion chiller. It was an 11gallon batch and after putting the first 6 gallons or so into the first carboy, I noticed the same thermometer started to creep up in temperature. By the time the second carboy was halfway full, the temperature reading was 140F!! The wort was definitely hotter than that in my first carboy. Any ideas on what happened?

Leave the burner on? Or was it just somehow carry over from the burner?

Could the thermometer probe have been in direct contact with the chiller?

Were you taking the reading from the watercoming out of the chiller? I've seen people on here do that. I thought "DUH, easier than putting the thermometer in the owrt risking contamination. But then soon realized that pushing my water througha s slow as I could with my hose still on, the water was still much cooler than the wort. The water temp was way cooler than that of the wort.

Were you draining your wort from a spigot at the bottom of the kettle? Because maybe the immersion chiller left the wort at the top of the kettle warmer than at the bottom. I have noticed with my immersion chiller that since the chiller sits at the bottom of the kettle, and only goes up like 1/3 of the height of the kettle, the kettle, and therefore the wort, is much cooler at the bottom, where the chiller is.
So maybe you had the same thing, and you were draining off the cooler stuff at the bottom, leaving the hotter stuff at the top.

Gotta stir.

stretch that IC out a little, and get a good swirl going while cooling(no splashing).

I'd say your kettle was stratified and the wort above the chiller never cooled off.

david_42 said:

I'd say your kettle was stratified and the wort above the chiller never cooled off.

Click to expand...

A delta of 60* is pretty extreme though. If I had to guess, I'd say that your thermometer might possibly have gotten stuck.

Then again, you were doing at least 10 gallons of wort it sounds like, so it's possible I guess. That's a pretty heavy stratification though. 20 degrees I'd say sure, but 60?

Having done some experiments, I can say that a delta of 60F isn't extreme, even in 5 gallons, if the chiller is short.

Must stir kettle!

First time I did a full boil the temp went down pretty fast. then I felt the side of the pot. The top had cooled down nicely but the bottom was still pretty hot.

The thermometer was in direct contact w/ the coil and there is probably 3-4 inches of space below the immersion coil-- not much above though. Next time I'll keep it on while I drain out wort through the chiller to make sure the hot stuff doesn't just go uncooled. It also seems unanimous that I need to stir-- maybe time for a Jamil Whirlpool chiller.