Are Refrigerator Fans Variable Speed?

Rationale

• The rationale for a variable speed fan in refrigerator units is fairly understandable. Because older models tend to operate on the "all or nothing" principle, they require a considerable amount of energy to start from a dormant position. Those refrigerators have to spend energy on the start-up of the compressor motor and fans at the same time in order to quickly cool the refrigerator. Older refrigerators also have to run for longer periods to compensate for the transfer of cool air. Variable speed fans, in conjunction with other variable speed components, operate more efficiently by remaining on at lower speeds and simply changing those speeds as necessary.

How It Works

• Microprocessors serve as the brains for new and more energy-efficient refrigerator models. Refrigerators have sensors that tell the microprocessor when the fans need to kick on and circulate cold air throughout the refrigerator. The sensors tell the microprocessor how the refrigerator is being used so that it can analyze and determine how the fans should be operated. This results in the refrigerator having a steady stream of cool air as needed.

System

• The use of variable speeds in refrigerator systems is not limited to just running the condenser and evaporator fans at varying speeds. Instead, the microprocessor's control of these systems has an effect on the entire refrigerator as a whole. For instance, because of the constant temperature levels throughout, the compressor does not need to turn on and off on a regular basis. This saves on the life of the compressor and the compressor motor. Many of these now operate at variable speeds as well.

Integration

• Modern refrigerators integrate the use of multiple fans operating at variable speeds. Aside from those that cool the main refrigerator compartment, some fans separately cool the freezer. Some refrigerators now have separate fans for various compartments as well. For instance, a fresh food drawer will often have its own fan that operates at variable speeds to keep fruits and vegetables at optimal temperatures.