Customer Questions and Answers for Refrigerator Adaptive Defrost Control Board by Whirlpool

Dave, Right above the crisper drawer there is a vent on the left wall between refrigerator and freezer. You will want to make sure that the vent is not clogged with ice. If it is you will need to clear the ice. The best way to clear without damaging the Styrofoam insulation is to use hot water. Once clear check to make sure that there is air flow through the upper vent.