Refrigeration
Refrigeration is a common phrase as we all use a refrigerator for keeping food items from spoiling. The process of refrigeration is also utilized for the homes air conditioning system. A large misconception though may be the fact that refrigeration does not make things cold. Refrigeration removes heat and in the absences of that heat only cold remains.
The blood of any refrigeration system is the refrigerant or carrier of the heat. The refrigerant can come in the form of Freon, Ammonia or even Propane. The purpose of the refrigerant, regardless of the type, is to carry absorbed heat from one location and deposit it in another. In the case of the home refrigerator, the refrigerant absorbs heat from the interior insulated box and deposits that heat outside of the box. The coils located behind or below the refrigerator are called the condenser coils.
The condenser coils deposit any gathered heat to the outside of the refrigerant system. You may note that the rear of the refrigerator is always warm when you hear the compressor operating. The compressor is the heart of the refrigeration system. It takes the refrigerant and moves it from the high side, high pressure, to the low side, low-pressure portion of the sealed system.
Connected to the low side of the system are the evaporative or absorbing coils. These coils are located inside the refrigerators insulated box. These are the coils that feel cold to the touch of your hand. The evaporative coils absorb the heat from the items in the refrigerator, and as stated above once the heat is removed only cold can remain.
The sealed cycle of the refrigerant system is all powered by the compressor. The compressor pulls the refrigerant, as a liquid, through the evaporative coils where the refrigerant gathers heat from the items inside the box. As the liquid refrigerant gathers heat, it turns from a liquid into a gas. The gas refrigerant carries the heat away from the interior of the insulated box. The gas then passes through the compressor and is pushed into the condenser coils at a high pressure. In these coils the heat is released. During the releasing of the captured heat, the gas refrigerant then "condenses" back into a liquid. The liquid refrigerant is then "sucked" back into the evaporative coils to repeat the cycle and gather more heat.
All refrigerant systems operate on this very principle of gathering heat in a liquid form. After heat is absorbed it expands into a gas, the compressor then moves the gas into the condenser. Where the captured heat is released and the refrigerant moves back into the system as a liquid. Larger commercial systems will use large cooling towers to accelerate the condensing process. These cooling towers will use high volume air fans and water pumps that spray water onto the condenser coils. The two forces of air and water quickly aids in condensing the gas back into a liquid.
