"A refrigerator compressor runs less frequently when the refrigerator is full than when it is empty."

Assumptions

  1. When the compressor is not running, the condenser coils are at room temperature.
  2. A rise in temperature detected on the condenser coils indicates operation of the compressor.
  3. A return to room temperature indicates the compressor has ceased to operate.

By collecting temperature data over a period of time, and analyzing it according to the aforementioned assumptions, we can determine how frequently the compressor runs.

Site Specific Assumptions

  1. Room temperature will not affect the experiment because it will be kept constant.
  2. Outdoor conditions will not affect the outcome of our experiment because the refrigerator is not located adjacent to an exterior wall, nor is it located near a window.
  3. Contents of the freezer will not affect our experiment because nothing will be added to or removed from it during testing.

Inquiry Questions

A dearth of knowledge exists concerning why a refrigerator would have a lower cooling load when full than when empty. We identified two questions about why a full refrigerator may maintain coolth better than an empty one.

  1. Does the thermal mass of water laden foods (or jugs of water) play a role in heat storage, contributing temperature stability to the refrigerator compartment?
  2. Does the combination of thermal mass and the volume of stored items insulate against heat gain from outside the refrigerator?