How Whirlpool Refrigerators Operate
All refrigerators, including Whirlpools, circulate liquid coolant through the refrigeration system. Before the coolant reaches the freezer, it passes through an expansion valve. This expansion valve causes the liquid to expand into a gas in the freezer chamber, lowering the temperature. The cold air in the freezer then makes its way down into the refrigerator cabinet. After the coolant passes through the freezer, it is pumped through a compressor, which compresses the gas back to a liquid.
The purpose of the drain tube in your Whirlpool Refrigerator is to direct water into the refrigerator during the defrost cycle. As the freezer defrosts, the ice built up along the inside of the compartment heats up and melts, transforming into water. The sloped floor of the freezer compartment directs the melting water to the drain tube. Once in the tube, the water passes into the drain pan underneath the refrigerator, which catches all the water.
If your drain tube is constantly freezing, this is a good sign that your refrigerator compartment is set to the incorrect temperature. This, in turn, could be causing the water draining out of the freezer drain tube to turn into ice before it reaches the refrigerator compartment. According to the United States Department of Agriculture, the correct temperature setting for a refrigerator should be below 40 degrees Fahrenheit. Because you want to keep both the tube and the food in your refrigerator compartment from freezing, the correct temperature should be between 33 and 39 degrees Fahrenheit. This will be cold enough to keep your food at the proper temperature, but warm enough to keep the drain tube from freezing.
Cleaning Out a Frozen Tube
Remove the food from your Whirlpool refrigerator and store in another refrigerator. Remove the crisper drawers and lower shelf. Start the defrost cycle on your refrigerator. Keep an eye on the drain tube in the bottom of the cabinet. Keep any food debris out of the drain opening. Break up any ice frozen on the tube inlet with a sharp wooden implement, such as a chopstick. Don't use anything metal, as this could scratch the drain tube and give bacteria a place to breed and cause odors in your refrigerator.