Your refrigerator has a defrosting hose that leads to a drain pan under the unit. During the defrosting process, the fridge’s temperature increases, causing frost and any ice to melt. This is the first transformation, from solid — the frozen state — to liquid, when it becomes water. Thanks to its liquid state and gravity, the water enters the drain and travels down the hose. It ends its journey in the drain pan. If you find standing water in the fridge, the drain line may be blocked.
Normally, the water in the refrigerator drain pan disappears. The pan is located out of sight under the unit, so the process is invisible. Water left in a pan eventually evaporates on its own, and in the case of your refrigerator's drain pan, the warmth and air circulation from the compressor's fan speed up the process. An old or malfunctioning refrigerator may have water buildup in the drain pan, requiring you to empty it. If you smell mold or see water coming from under the fridge, remove the panel below the refrigerator door and check to see if the pan is overflowing or out of position.
Defrost a refrigerator manually that does not have a defrost button and that does not have any noticeable ice build-up by simply turning off the refrigerator and unplugging it from the wall.
Prop open the door to the refrigerator and watch for it to achieve room temperature. Lay a towel on the floor underneath the door of the refrigerator to catch any water or condensation that might come out of the refrigerator while you defrost it.
Clean the inside of the refrigerator once it is completely at room temperature and close the door.
Defrost a refrigerator that has an ice build-up in the refrigeratorr itself or in the freezer by first turning the temperature on the fridge and freezer to a setting that is about two levels warmer than it has been.
After three hours, use a knife or sharp stick to chip away at the ice, which should be softer. Remove the ice in this way and place it into the sink.
Turn the refrigerator and freezer two more levels warmer. Repeat the process in about three hours. Then, turn the refrigerator completely off.
Lay towels down on the floor because the condensation will seep out of the refrigerator as it defrosts. Monitor the refrigerator every hour and remove wet patches, chunks of ice or debris as you see them.