Air-conditioner Music / Mnemonics

I was forty-years-old, when sat down (because mental math isn't very good any more) to analyse the structure of the temperature configurators on common air-conditioner remote controllers.

Here's the math :

- - the typical controller allows for settings from 16C to 30C

- - this is divisible into three brackets of 5C each

- - - 26 to 30 C, median 28C

- - - 21 to 25 C, median 23C

- - - 16 to 20 C, median 18C

So these are the fundamental pivots.