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Physics

Why Leaving a Refrigerator Door Open Heats the Room

Quick fact

Leaving a refrigerator door open will warm the room, not cool it. In fact, a refrigerator with its door open acts like a small space heater, because the heat it removes from its interior plus the heat generated by its compressor are both dumped into the room.

Why this is interesting

You’ve probably been told that leaving the refrigerator door open will cool the room—but it actually does the opposite. Why does this common intuition lead us so wrong?