Your Freezer Questions Explained

Most modern residences feature one or more freezers. A freezer is cold enough to prevent most bacteria and fungi from multiplying, thus preserving any perishable items placed inside. Today, freezers come in many shapes, sizes, and efficiencies to serve many needs.

Refrigeration and freezing are ancient concepts based upon the fact that food spoils more slowly at lower temperatures. This is due in part to the temperature-dependency of microbial metabolisms – the colder, the slower. The modern freezer is a distant cousin of what was known as an “icebox” – an enclosed space, sometimes an entire warehouse, where food was kept with ice to keep it cool. Iceboxes and icehouses were very common before other means of refrigeration were discovered.

Most modern freezers utilize a vapor compression cycle to keep their contents cool. This cooling system is simple and can be easily understood. It simply consists of two coils of tubing – one inside the freezer, and the other on the outside – as well as a compressor. The tubes are filled with a refrigerant, which is a fancy word for a gas with qualities that are desirable to make this process run smoothly. Historically, freon has been used – however, due to ozone depletion from the release of CFCs, freon has been largely substituted by R-134A or ammonia. In any case, the refrigerant is kept as a gas in the tubing. The compressor pressurizes the gas, which causes it to heat up.

The hot, high-pressure gas flows though the coil outside the refrigerator where it cools and condenses into a liquid. It then flows into the coil inside the refrigerator where it encounters a larger tube and a lower pressure. This low-pressure region causes the refrigerant to boil back into a gas, absorbing a large quantity of heat in the process and becoming quite cold. After the interior of the freezer has been cooled, the refrigerant returns to the compressor to repeat the process. 

Of all the freezers in existence, the most efficient are chest freezers. There are two contributing factors to this: First, the compressor is closer to the cold space which puts it under less load. Secondly, cold air is more dense than hot air and will therefore sink. Opening the door of a vertical freezer will cause all the cold air to spill out. However, a chest freezer will retain this air and will help to save energy. For this reason, chest freezers are beneficial during power outages. To further conserve energy, the exterior coil should be well-ventilated and the compressor should be in good working order and Energy Star compliant.

Check out our favorite Best Chest Freezers 2016

Igloo FRF472 Chest Freezer, 7.1 Cubic Feet, WhiteCheck PriceHaier HF11CM10NW Chest Freezer, 11 Cubic FeetCheck PriceSummit CF07L 7.0 Cu. Ft. White Chest Freezer – Energy StarCheck PriceHisense FD90D6AWD Dual Zone Chest Freezer, 9 cu. ft., WhiteCheck Pricemidea WHS-65LSS1 Single Reversible Door Refrigerator and Freezer, 1.6 Cubic Feet, Stainless SteelCheck Price