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Polar King Walk-In Guide: What is Cold?

There is a common misconception as to how the heating and cooling processes actually work. Many people believe that temperature control is essentially pumping either hot air or cold air into an area. However, in regards to refrigeration, cold is actually the removal or transfer of heat. This process is accomplished by a number of methods such as conduction, radiation, or convective circulation. In essence, the cooling process actually removes or absorbs the heat from inside a refrigeration unit, such as a Walk-in Cooler or Walk-in Freezer.     

So what exactly is cold? 

According to the book Modern Refrigeration and Air Conditioning, by Althouse, Turnquist, and Bracciano “Cold means low temperature or lack of heat. Cold is the result of removing heat. A refrigerator produces “cold” by drawing heat from the inside of the refrigerator cabinet.” (Althouse, Turnquist, and Bracciano) In other words, in the refrigeration process, the heat is physically removed from inside of the unit. Additionally, “The refrigerator does not destroy the heat. It pumps heat from the inside of the cabinet to the outside. Heat always travels from a substance at a higher temperature to a substance at a lower temperature (second law of thermodynamics). Heat cannot travel spontaneously from a cold body to a hot body.” (Althouse, Turnquist, and Bracciano)


How does your Walk-in unit get cool?

Once the internal temperature of your walk-in cooler or freezer has risen to the set point, the thermostat closes and signals the compressor and condenser fan to turn on. During the cooling cycle, the evaporator pulls warmer air from inside of the unit. As the air passes through the evaporator it is cooled and blown back into the unit via the condenser fan. Once the thermostat reaches the desired temperature, the thermostat shuts and the compressor and condenser fan are signaled to shut off.

As the industry’s #1 manufacturer of seamless fiberglass outdoor Walk-In Coolers and Walk-In Freezers, Polar King units are designed to endure even the most rugged conditions and climates. All of our outdoor Walk-In Coolers and Walk-In Freezers are delivered fully assembled and require only a simple electrical connection to put them into operation. With a 100% seamless fiberglass design, Polar King offers the industry’s only one piece, outdoor units. To learn more about the fiberglass advantage, contact Polar King today!