Functions of an Evaporator

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An evaporator cools air.
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An evaporator is a device used to cool air. It is part of a cooling system found in freezers, refrigerators and air conditioners. Evaporators are responsible for the cool air that comes out of the vents. The evaporator's cooling mechanism uses heat to do the job. Failure of the evaporator can lead to problems with the entire cooling system and damage some of your furnishings if the problem isn't contained.


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The Facts

Coils transform liquid to gas.
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The evaporator coils are used to transform the refrigerant from a liquid to a gas. It is the last device in the cooling system. To accomplish this, the evaporator allows the fluid refrigerant to expand with lower pressure in the coils. As the liquid expands, it loses heat. A fan blows warmer air over the coils and that air become chilly and flows out the vents.



Open refrigerator and freezer.
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The evaporator is responsible for the air that cools your house, car and business and flows through our refrigerators and freezers. Evaporators are the last link in the cooling system chain, and its location is usually on the inside while the other parts are on the outside. That makes it much simpler to reach if problems arise. Many problems with an evaporator are easy to dissect and fix due to the simplicity of the device.



Air vent.
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Evaporators use the heat around it to produce the cool air coming out of the vents. When the refrigerant, a fluid used throughout many cooling systems, leaves from the compressor, it goes through a tiny hole as a liquid. The low pressure of the evaporator allows the refrigerant to expand and cool down, becoming a gas. As this is happening, a fan is blowing warmer air from around the cooling system over the coils filled with the cooler gas. The gas catches the heat molecules, creating condensation on the coils. As the air blows over the coils and through the vents, the air becomes much cooler. The gas in the evaporator coils continues to the front of the cooling system and repeats the process until the set temperature is reached.



Beware of damaging carpet.
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The evaporator is just as important as the other parts of the cooling system. Although the last link in a cooling system, it is just as important as the other parts. Usually if there are any problems with the temperature of the air, it can usually be traced back to the evaporator. Leaks from the coils not caught by the flow pan can damage furnishings such as carpets, curtains, furniture and ceiling tiles if the cooling system is high enough. If the pressure or the temperature affect the ability of the liquid's transformation, the remaining fluid can damage other parts of the cooling system that is expecting gas to arrive.



Thermometer should be kept above freezing.
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One of the common problems with an evaporator is the coils freezing over. This happens when the temperature in the evaporator falls to 32 degrees or lower. Several causes of this is restricted air flow, indoor temperature being too low, an undersized liquid line and an oversized compressor. This stops the condensation from the air flowing over the coils from leaking into a pan. The condensation freezes on the coils, and the more condensation that builds up, the more ice will form. Another problem is with a perfectly working evaporator. If there is a foul smell, it could signal a fungus is growing in the coils. This problem comes from the moisture remaining in the coils for a period of time. A car's AC is most prone to these complaints. Cleaners such as Lysol will get rid of the fungus.


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