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Expansion Valve

The expansion valve (also known as the thermal expansion valve) regulates the flow of refrigerant entering the AC evaporator, which transforms the refrigerant into cool air for your vehicle. It is attached directly to your AC system’s liquid line and also has a sensing bulb connected at the top. The sensing bulb helps regulate the pressure of the refrigerant and prevents the refrigerant from overflowing back into the condenser. Your expansion valve is an integral part in allowing cool air to flow from your AC system to your vehicle’s cabin.

Signs of a bad expansion valve

There is only one sign that your expansion valve may be faulty and that is if the air from the AC system is no longer as cold as it should be. This typically means that the expansion valve is having issues getting enough refrigerant to flow into the evaporator. Issues with refrigerant pressure regulation will cause less of it to enter the evaporator and get transformed into cool air. This may also be due to refrigerant overflowing back into the condenser, which is an issue typically associated with a bad sensing bulb.

Expansion valve maintenance

If you are having trouble getting cool, consistent air from your vehicle’s AC system, it’s time to get your expansion valve inspected and repaired by a car care professional. The best way to get maintenance and repairs done on your vehicle’s AC system is to book an appointment through CarAdvise. CarAdvise makes car care simple and guarantees that you’ll pay less than the shop price for all services.

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