After completing repairs on a freezer, why might the temperature stop dropping at 35 degrees?

The scenario of a freezer stopping at 35 degrees could be accurately explained by the system removing latent heat instead of sensible heat. In thermodynamics, latent heat refers to the heat absorbed or released during a phase change of a substance, such as the transition of refrigerant from liquid to vapor in the evaporator coils. When the evaporator is primarily removing latent heat, the temperature may not drop below the freezing point, as the energy absorbed is used to convert the refrigerant rather than to lower the temperature of the internal environment.

In contrast, sensible heat involves temperature changes without a phase change, which is essential for continuing to drop the temperature below 35 degrees. If the system is not functioning optimally in terms of handling sensible heat, it can result in inadequate cooling.

This choice explains why the freezer might not be effectively lowering its internal temperature, reinforcing the overall importance of proper heat exchange in refrigeration systems.