Have you had your AC recharged?
Was it evacuated and replaced recently. Usually thats what will help you get ice cold hair is an AC recharge.
Perhaps the new sensors are faulty.
I'm not a tech, but I hope that helps.
'92 300CE - Sold
2004 C240 - C7 Wheels
2015 ML350 - P1, Pano, Ash poplar wood, Sport Dinamica interior, Running Boards Keyless go.