Airconditioning Cooler Regulation?

[powerjunx]

Got here Aircon unit with old documents. Pages were torn and more missing.
Attached pic, i found page with Graphical Cooler Regulation??? Anyone plz elaborate what this mean?
It's a Standard ARP of York Refrigeration, Marine & Controls.
Comments well appreciated.

"..the more, the merrier" Genghis Khan

 

[MintJulep]

Basically it seems to say that if it's too warm cold air comes out and if it's too cool warm air comes out.