ACE Microbrewery

[531Man]

What you are doing when you alter the temp is calibrating the machine as if the temp display to actual temp is out so it is the machine that has the temp altered and not a single stage

Got it.
Thanks again for putting it so succinctly.
I think I have my head around it now.
Of course I could avoid all this and just drop the set mash temp. by my observed over-read.
Would obviate a whole load of button pressing.