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Hvac Contractor: Commercial Refrigeration

Commercial Refrigeration: What is it?

Refrigeration is best described, as a process, by the removal of heat from a space or substance, thereby cooling it. This process does not refer to the active cooling of a space or substance, but to the extraction of heat, which creates cold. (Artificially creating cold temperatures is formally called cryogenics, not refrigeration.) To begin understanding the complicated, but innovative process of refrigeration, it’s necessary to understand its breakdown-its components. The most widespread kind of refrigeration today is through a vapor compression cycle. The main components are the compressor, the condenser and evaporator coils, and the expansion valve. There is the vapor to be compressed; a compressor to compress it; the condenser coil; the expansion valve; and the evaporator coil. First a gas coolant is compressed. It heats up because of the immense pressure put upon it. Then the very hot compressed gas pass
es through a condenser coil, where it condenses into a liquid. This liquid passes through the expansion valve, where its pressure is reduced and the liquid is cooled through the process of adiabatic expansion. The cooled liquid now goes through the evaporation coil. As air blows over the coil, the refrigerant absorbs heat and cools the air. The liquid boils and turns to a vapor. Because of this evaporation, its temperature can drop to as low as -27 degrees Fahrenheit. The vapor recycles into the compressor to begin the process anew.

The basic purpose of refrigeration is not to keep perishable foods cold. Keeping them cold is the means to the end, and that is to slow the growth of bacteria on the food. This is what preserves perishable food: The retarding of any organic growth that could begin to break down food, thereby making it inedible. Now it takes longer for food to go bad, which means a significant increase in shelf life. If a bottle of milk were left on a counter at room temperature for two or three hours, it would surely sour. But milk can last two to three weeks under refrigeration. Food stays fresher longer. That means more food is for sale longer.

Who it’s for:

A great number of foods are perishable. Without the aid of refrigeration, store owners and restaurateurs would be extremely limited to a small number of foods to serve or sell. Bananas, apples, pears, oranges, peaches, and other fruit; meats, cheeses, eggs, and milk; sauces, gravies, and dips are a small group of the many foods that a proprietor in the food business would want to refrigerate. But the uses of this necessary modern technology extend to the vintners’ world, too. Reducing the temperature of wine can prevent yeast from continuing to grow and carbon dioxide from evolving. Therefore the wine remains largely intact as the vintner meant it. It will not become more alcoholic. It will not take on properties of carbonization that would otherwise undermine the integrity of the vintage.

Its benefits and disadvantages:

Refrigeration prolongs the life of a various number of important foods. Without this process, these foods could quickly yield to the destructive forces of bacteria and decay. Contemporary refrigeration systems use refrigerant compounds that contribute either slightly or not at all to the depletion of the ozone layer. These are hydro chlorofluorocarbons (HCFCs)-which contribute to a lesser degree to ozone depletion, and hydro fluorocarbons (HFCs)-which do not contribute to ozone depletion. Before the widespread use of these compounds, chloro fluorocarbons (CFCs) enjoyed popularity. But CFCs contribute significantly to ozone depletion. Even though HCFCs and HFCs tend not to threaten the health of the ozone layer to the extent of CFCs, they still maintain what is called Global Warming Potential, or GWP. When choosing a refrigerant to use in your commercial refrigeration unit(s), keep in mind two serious factors. One is the “direct effect,” or the immediate impact the refrigerant could have on the surrounding environment or atmosphere if it leaks. Secondly, think about the amount of energy necessary to operate your refrigeration system. Overall, HFCs are the optimal compound. They are largely energy efficient, contain low levels of toxicity, and they can be reused. They have a high rating of what’s called “Life Cycle Climate Performance” (LCCP). In the case of HFCs, low LCCP means they consume low levels of fossil fuel, and thus they are responsible for low levels of carbon dioxide emissions, a key factor in manmade greenhouse gases

By: Priyank Saxena

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Jon Ellowitz is a writer for Yodle, a business directory and online advertising company. Find a contractor or more home care articles at Yodle Consumer Guide. HVAC Contractor: Commercial Refrigeration

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