How a Refrigerator Works

Explains how a refrigerator uses the vapor-compression refrigeration cycle to remove heat from its interior and reject it to the surrounding air, with practical diagrams of common layouts (top‑freezer, side‑by‑side, and French‑door models, sometimes with dual evaporators). The cycle centers on four components: compressor, condenser, expansion device (capillary or expansion valve), and evaporator. The compressor pressurizes refrigerant gas, raising its temperature; the condenser coils and fan shed that heat and condense the gas into a high‑pressure liquid; a capillary tube or expansion valve drops the pressure so part of the liquid flashes to vapor and cools the remaining liquid; the cold liquid/gas mixture absorbs heat in the evaporator as it vaporizes while an evaporator fan circulates interior air; the warmed low‑pressure vapor then returns to the compressor. Temperature is regulated by thermostats and sensors that start and stop the compressor.

Also covers practical specifics useful for troubleshooting and repair: how condenser and evaporator fans affect heat transfer, the functional equivalence of capillary tubes and expansion valves, and why refrigerant properties (low boiling point, high latent heat and critical point, low viscosity, adequate density, low toxicity, cost) matter. Uses analogies - a sponge being squeezed and human sweating - to illustrate phase‑change heat transfer, and summarizes the system as a loop that repeatedly moves heat out of the cooled space.