Living in the desert presents many challenges, but none are so difficult to overcome as the intense, furnace-like heat of the summer. Fortunately, modern air conditioners are constructed with just a few parts, which makes them incredibly reliable. You can count on your unit to keep on trucking for years and years with very little maintenance, but if your air conditioner suddenly refuses to start up one day despite your best care, the capacitor is probably to blame. Though small, capacitors play a big role in your air conditioner’s daily functioning.
What is a Capacitor?
A capacitor is a clever device composed of two metal conductors separated by an insulating material. On an air conditioner, they often look like large, cylindrical batteries with two or three posts sticking out of the top. The main job of capacitors is to store electrons to provide start-up energy for your air conditioner, they build up a charge when electricity runs through them by swapping electrons between the two conductive plates inside.
Because of their capacitors, air conditioners do a little magic trick every time they start up. Your A/C unit actually requires a great deal more start-up energy than is available through your home’s wiring, so the capacitor is added to the circuit to give an electrical jumpstart at the same moment that your air conditioner is drawing power from the electrical grid. Together, these two electrical sources provide the right amount of juice to your air conditioner. The capacitor’s job is over until an air conditioning cycle is complete. Then the compressor must start up again.
Your air conditioner may actually contain several different capacitors, including the compressor motor run capacitor, the outside fan motor run capacitor, the indoor fan motor run capacitor and the start capacitor. The most common capacitor to fail is the compressor motor run capacitor. It has a big job, and an even bigger footprint in your air conditioner. It’s actually a dual capacitor, with three terminals instead of just two.
Why Good Capacitors Go Bad
Capacitors fail every day — they do a tough job and, unfortunately, their work takes a toll. There are a few factors that play heavily into the lifespan of your capacitors, though. These include:
Heat exposure. In Phoenix, perhaps one of the most damaging elements for air conditioner capacitors is the heat. Unfortunately, exposing these units to high heat for extended periods greatly shortens their lives and can cause significant damage to your unit. Make sure you shade your air conditioner. Keep it clean and the air circulating to maximize your capacitor’s lifespan.
Voltage rating. All capacitors have a voltage rating, which informs air conditioner technicians exactly which capacitor matches which air conditioner. Unfortunately, homeowners may try to cut costs by choosing to replace their capacitor themselves without understanding how to choose the right capacitor. An undersized capacitor won’t hurt your air conditioner, but it will shorten the capacitor’s life significantly. If you decide to DIY this job, remember that bigger is better — if your air conditioner is a 370- volt unit, bumping up to a 400-volt capacitor will ensure you get enough power and that your capacitor comes closer to reaching its maximum life span.
Age. Like all things, capacitors have a limited life span. Most are designed to last approximately 20 years, but a number of factors can cause them to wear out more quickly. If your air conditioner cycles much more rapidly than average, your capacitor is undersized (as mentioned above) or it’s built from problematic parts, and the estimated life span may be greatly reduced. Fortunately, these parts are relatively inexpensive to have replaced, so even if your capacitor wears out before your air conditioner does, it won’t break the bank.
If your air conditioner is refusing to start, running with little enthusiasm, making weird noises or just isn’t cooling right, give Precision Air a call. All of our technicians are NATE certified and trained to handle any sort of problem your air conditioner can throw at them. Remember, we don’t charge weekend fees or add trip charges to your bill, and we’ll come out when it’s convenient for you. A quick call to 602-349-6922 is all it takes to schedule your appointment, 24 hours a day, seven days a week!
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I wanted to make sure my air conditioner was ready for summer. Fernando came out and made sure my unit was tip top. He was friendly, professional and not a sales man. Thanks Fernando!
Colin and Andrea were incredibly professional and knowledgeable. They did a great job representing the company. We will definitely contact them again for any HVAC needs that arise.
We woke up in the middle of the nite on memorial day to a hot house. I called precision at 6am and they were here before noon. Simple problem fixed, cool house. I love these guys!
Thank you Ray at Precision Air...the compressor on our AC went out last night and the house was HOT. This morning Ray was there to replace the compressor and had us feeling the cool air again in no time. Great customer service...quick response time and friendly from the first call until the repair was completed. Ray even offered to clean the filters! Thank you!!
I’m so glad I called Precision for my annual AC checkup!! Austin was professional, super friendly and answered all my questions. I’ve had more bad experiences with AC companies here in the valley than good ones. Precision Air will have all my hvac business going forward!! Thanks for being a reputable and honest company!!!
He did a great job; professional and knowledgeable! Kalin is the technician’s name and Precision Air and Plumbing should take a bow for hiring such an invaluable employee!!!
Precision Air is a company of integrity. I signed up with them August 1st, 2019 for their AC maintenance plan for 2 years... Someone from their office called me a week ago to set up their yearly maintenance visit. SO GRATEFUL.
Precision Air and Plumbing is a wonderful company to work with! They are very experienced and professional. They have helped us in our home for many years via a/c service and air duct cleaning.
It was time to replace our AC, and so our choice was Precision Air, as we've been with them for over 20 years. Teman & Julian did an excellent job on the installation today, arriving on time.