Hello everyone. My side by side whirlpool has the following problems/symptoms: the Ultimate Chill Zone Rotary Control Knob keeps freezing up. The freezer is staying cold, but frosting up, & the fridge doesn't seem to be cooling as well. Any recommendations as to what is going on, how to diagnose the problem, or what part or parts are bad & need to replaced replaced, would be appreciated. This is my 1st post to this website, so I'm a newbie here. Thanks for any help, anyone might offer.