What Is a Refrigerator Defrost Drain?

The small drain opening at the lowest point of a frost-free refrigerator or freezer compartment. Several times a day the appliance heats its cooling coils to melt frost, and the meltwater runs through this hole down a tube to an open pan near the compressor, where it evaporates. The hole is small, cold, and sits directly below the food, so it plugs easily with ice or crumbs, and a plugged drain shows up as water pooling under the crisper drawers.

Clearing one is a 30-minute job with warm (not boiling) water and a turkey baster: flush the hole until it swallows water as fast as you pour. An ice plug melts through in a few minutes of flushing. A debris plug may need a pipe cleaner worked gently into the opening first. A spoonful of baking soda in the last rinse keeps the drain line from souring.

Location varies by design. Most top-freezer and many side-by-side models hide the drain behind the rear interior panel of the freezer, while bottom-freezer and single-door fridges usually put it at the back of the fresh-food section, under a small snap-off cover behind the drawers.