Customer Questions and Answers for Refrigerator Defrost Timer by Whirlpool

Jason, It doesn't sound like a defrost timer or heater. possibly a defrost thermostat, but not likely. It actually sounds like you have a clogged defrost drain tube and a block of ice in the drain pan. You'll need to remove the back wall of the freezer and clear the clog and ice in the drain pan. As for frost on the shelves and door, you could be spraying the defrost water, but check and make sure the dispenser door closes and seals, and the door gaskets seal against the front flange of the fridge. Good Luck.