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What Does the Expansion Valve Do in an Air Conditioning System?

The modern air conditioner is quite a marvel of engineering. The complex working of its components is the reason that only professionals can effectively diagnose and repair a malfunctioning air conditioner.

One of the key components allowing an air conditioner to work is a part called the expansion valve. Without this valve, an AC would not be able to draw sufficient heat from the inside of a home.

How the expansion valve helps cool down your home

In order to explain the purpose of an expansion valve requires first explaining the basics of how refrigerant works in an air conditioner. Refrigerant is a heat transference fluid that shifts between liquid and gaseous state, absorbing and releasing heat as it does so. When the refrigerant moves through the outdoor condenser coil, it releases heat to the outside. Cooled down, it then moves toward the indoor evaporator where it absorbs heat.

However, at the point after leaving the condenser, the refrigerant—which is in a high-pressure liquid form—is still too hot to effectively go carry out the process of evaporation that will draw heat out of the indoor air. This is where the expansion valve does its job: the valve is designed to remove pressure from the refrigerant and rapidly cool it down into a cold gas. The valve doesn’t remove heat, only pressure—but removing the pressure has the effect of lowering the temperature of the refrigerant. After it leaves the valve, the refrigerant will be at its the coldest. The refrigerant is now ready to move through the indoor evaporator coil, where it will meet warm indoor air and through evaporation lower the temperature of the air.

Live any component inside an air conditioning system, the expansion valve can malfunction, leading to an AC that won’t provide any cooling. Always call on professionals to look your air conditioner when it encounters trouble: a number of different malfunctions might lurk behind the problem, and it takes training to locate the actual cause. If a broken expansion valve is at fault, the technician will repair or replace it.

Call Malek Heating & Cooling in Evanston, IL when you need fast air conditioning repair. We offer 24-hour emergency service.

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