Herms And Temp Probe Position

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I'm going to build a HERMS (or eventually RIMS) heater to have a better temperature control. I'll use it for both, traditional mash and BIAB.
Reading a lot of threads I still have this question not answered.
The temp probe that control the PID where has to be placed?

I found three options:
1. At the exit of the Herms
2. at the inlet of the Herms
3. inside the mash

The option 3 should give the best control, followed by option 2. Both have the problem of not controlling the temperature at the exit of the heater. This could lead to the problem of having the worth temperature higher than 70 so deactivating the enzimes (or is it only my concern and really this don't happen?).
1 controls the max temp of the worth but it's limited to the target temp so the mash will never reach the target temp.

What is the solution that works for you and what problem did you experience as stability, get on target, ...

An additional solution could be put the probe in the mash and additionally contro the max temp inside the Herms, lets say 75. In this way I shoud get both the advantages.
This could work with Herms but not with Rims.

I need your help, my most critical question is if the enzimes are deactivated or modified it the worth is rised around 80 degrees in the path from the Herms and the mash (where it will mix with rest of the mash).




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at the return point into the mash, that way it's a close as possible to the mash, but not in the mash.

here's mine

the important thing to remember is you will learn your system and produce beer that you like from your system, you may find that 70 degrees give you a medium body and good attenuation where for me I may mash at 64 as there's where I know my system gives me the good attenuation/medium body

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