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AC Capacitor

ac capacitor

While you may use your air conditioner all throughout summer, you may not be familiar will the components that allow you AC to cool your home. Take for example the ac capacitor, although small they play an essential role in your air conditioner’s daily functioning. Capacitors make it possible for your AC to operate reliably and properly.

What are Capacitors?

Capacitors are electrical components that store energy and use it as needed. They are composed of two metal conductors separated by insulating material. Your AC may actually be equipped with several different capacitors: compressor motor run capacitor, fan motor run capacitor, indoor fan motor run capacitor, and a start capacitor. Without a properly working capacitor, your system will not be able to function properly. During AC repair calls the most common capacitor that fails is the compressor motor run capacitor.  

Start Capacitor

Your air conditioner requires more start up energy than is available through your home’s wiring. A start capacitor is included as part of the circuit to provide an electrical jump start when you power on your AC to begin its cooling cycle. Together they provide enough power to start up the AC. If an AC start capacitor is faulty, you will most likely hear your system humming away without it ever starting up. This hard starting of the compressor puts extra strain on your system that could lead to costly repairs. If the capacitor alone cannot start up the system installing a hard start kit may be required.

Run Capacitor

An AC run capacitor help keep your system running properly. Unlike a run capacitor it does not provide extra energy, but it helps the system maintain a proper consistent charge. If you have a faulty run capacitor the system may start up but will cycle off before it should. This is also known as short cycling and leads to wasted energy, extra strain on your AC system putting it at risk for operational damages.

Faulty Capacitors

An air conditioner is a complex mechanical system with a lot of moving and electrical components. Eventually, and if you tend to neglect routine maintenance, your air conditioner will require AC repair. Furthermore, if issues are left unresolved, then it could lead to potential catastrophic system damage. A few reasons for failing capacitors are heat exposure, voltage rating and age. To maximize your air conditioning and avoid damage from heat exposure, keep it clean with proper air circulation. If the AC unit is in direct heat, consider shading it. All capacitors have a voltage rating that matches air conditioners. If you have an undersized capacitor then it will shorten the lifespan of the capacitor significantly. Most capacitors are designed to last years. However, if your air conditioner constantly cycles or is undersized the lifespan will be greatly reduced. Fortunately, capacitor replacement is an easy inexpensive repair that will not break the bank if it does fail.

Faulty Capacitor Symptoms

One of the most common signs of a faulty capacitor is a system that is not blowing cold air. An AC that has a delayed start or fails to start, humming from your AC, or an AC that shuts off on its own are symptoms of a faulty capacitor. Capacitor replacement is a quick repair that will not leave any serious effects on the HVAC system. However, if a faulty capacitor is ignored you may end up with a completely non-operational system on a day when you need it the most. For example, a motor connected to a run and start capacitor will still attempt to run even if both capacitors have failed. Eventually, the motor will overheat and burn out, which will require motor replacement. It is important you contact a professional as soon as you notice a motor that does not stay on or any humming or clicking sounds coming from your AC unit.

AC Repair Los Angeles

Contact LA Construction Heating and Air at 818-341-3406 or online we can perform AC repair and determine whether your AC issues are a result of a faulty capacitor. It is important to leave capacitor replacement to an HVAC professional who will be able to find the right replacement and handle components safely.

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