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Your Air Conditioner’s Expansion Valve Might Need Repair


Some of the components of your AC system are obvious and easy to understand. If we tell you that there’s a blower fan, and a motor which powers it, you will have already assumed as much. You also know that there’s refrigerant, which flows through coils throughout the system. But some air conditioner components are a little more mysterious.

The more you know about your AC system, the more empowered you will be to take good care of it and keep it running as well as possible for as long as possible. For this reason, we love to provide HVAC education to our customers.

Today, we’d like to tell you about your air conditioner’s thermal expansion valve, and how to know if it might require repair.

Your Air Conditioner’s Main Components

In your outdoor AC unit, there is a vital and expensive component called the compressor. It keeps the refrigerant flowing through the condenser coils—also in the outdoor unit—and the evaporator coils in the indoor unit. The other critical component of the indoor unit is the blower fan, with the motor which powers it. 

The refrigerant absorbs heat in your home while it’s flowing through the evaporator coils, which get their name because that heat causes the refrigerant to evaporate into a gas inside the coils. Then it flows out to the condenser coils, where it needs to release that heat and condense back to a cold liquid. How does it do that? With the help of the thermal expansion valve.

Pressure and Temperature

The primary function of your air conditioner is to release the heat that has been absorbed from inside your home. Only then can the refrigerant absorb more heat. But it’s hard to simply force heat out of a hot gas. Instead, the expansion valve releases the pressure.

When pressure drops rapidly, a natural consequence is that temperature also drops. The refrigerant condenses from a larger volume of hot gas to a smaller volume of cold liquid. Now it’s ready to circulate back through the evaporator coils and soak up more heat from your home.

Expansion Valve Problems

As you can see, the thermal expansion valve does an essential job. If something goes wrong with that valve, it will have serious consequences. It needs to be repaired right away, or it will put a lot of strain on the compressor. Since that is the most expensive component, you must do everything you can to keep it from failing.

Signs of a bad expansion valve include the compressor constantly running, warm air or air of inconsistent temperature coming from your vents, ice forming on the refrigerant coils, and strange noises. Don’t let these symptoms continue! If you notice any of these issues with your AC expansion valve function in Skokie, IL, get prompt repairs. 

Whether you’re ready to schedule a service appointment or you would like to learn more about your home’s HVAC system so you can keep it in the best possible condition, we’re always happy to help.

Contact ServiceMax with any questions about your air conditioner.

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