I don’t like probe in the boiling flask because of the temp difference between the heater temp and the probe temp. By the time the probe tells the heat to stop the outside of the flask is overheated. This is how people are killing stir bars and mantles through degaussing of the magnets by taking them to their curie temperature. Imagine a pot of boiling water, water will only boil at 100c, no matter how much energy you drive into the water. The water will only allow so much energy. Imagine a situation where it takes 100 energy units to boil a solution, the solution is controlled by a probe in the liquid. The heater starts by dumping 200 units of heat into the liquid, then the probe sees 100 and says stop. Then the probe seeing the liquid cool one degree says “give me another 200 until I say stop”. This can also contribute to pid overshoot.
Do you see the problem?
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