Originally Posted by samc
Doing my fourth BIAB on my new single kettle set up. First three brew days were pretty much uneventful but today I ran into a problem. I decided to do a 104F rest to check PH and adjust but my temps overshot to 111F before the grain went in.
Sounds like a PID setup problem. Just water, temp set for 104° and it hit 111°. Temp probe under FB which is also where the heating element lives. I'm assuming that you were recirculating during this heat up process. No? If not, that could be a root cause (stratification). If you were recirculating, then either the PID parameters are in question or the temp probe placement is not measuring the actual output temperature but is measuring an eddy current (a low flow part of the water stream - probe possibly placed on the opposite side of the kettle from the output port? That way it would tell the PID that the temp was not quite there and deliver more power.)
Anyway, Sorry for thinking out loud.