5 Reasons Your AC Won’t Turn On

An air conditioner that won’t turn on is aggravating. What does it mean? Can you troubleshoot it yourself? Will you have to break the bank for an unexpected costly repair? Is there anything you can do to prevent this from happening again in the future?

While there isn’t a “one-size-fits-all” answer to all of your AC questions, there are several common situations that can cause air conditioning system to shut down. Below, we list the likely culprits to an AC that won’t turn on and what you can do about it.

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10 Reasons Your Air Conditioner Won’t Start

1. Tripped Circuit Breaker

This is your home’s way of protecting itself from fires. If you’re doing laundry, using the dishwasher, baking a pie, and blasting your AC all at once, the power surge may cause a breaker to trip.

How to Troubleshoot: Before you panic, check to see if you need to reset a breaker. All switches on the panel should be labeled, indicating the part of your home it powers. Find the one that corresponds to your air conditioner. It’ll have three settings: “On”, “Off” and a middle neutral setting. Set it to neutral before switching it back to “On”.

2. Dirty AC Air Filters or Frozen AC Coils

Air conditioners work by absorbing the heat from your home. The moisture condenses and drips into a drip pan, which is then drained outside. For this process to work seamlessly, you need to change your air filters regularly. Otherwise, dirt accumulation will block airflow. As a result, instead of moisture dripping into a drip pan, the water will freeze on the AC coils.

How to troubleshoot: To verify whether or not this is the issue, turn off your air conditioner and shut off its power at the circuit breaker. Remove the cover to the AC. If you see layers of ice, use a blow dryer on its lowest setting to melt the ice faster. Once melted, wait for it to dry, then turn the power on again.

To prevent this from happening again, make it a point to change your air filters regularly. Frequency depends on many factors: How many people live in your home? Are there any allergy sufferers or smokers in the home? Do you have any pets? Do you burn scented candles? Do you live in a location with a lot of air pollution? If several of these circumstances apply to you, change the filter once a month.

3. Blown Fuse

Just as the case with circuit breakers, a fuse will shut off if there is too much electrical current going through the wires.

How to troubleshoot. The fuse box is a small square box on an outside wall of your home. You can open it by lifting up its metal lid. Pull the fuses out and use a multimeter to do a continuity test. If one of the fuses is not working, you can simply buy a new one at any hardware store.

4. Broken Thermostat

Some thermostat models require batteries. If you have this type, read its manual and set reminders to change the batteries every so often. Other reasons a thermostat screen is blank could be that there’s dirt inside the thermostat cover, wiring problems, or that you simply need to replace it.

How to troubleshoot. If the screen on your thermostat is completely blank, watch this video tutorial to find out if it needs to be replaced.

5. Faulty capacitor.

Most air conditioning units have a lifespan of 15 to 20 years. If yours is older than that, you may need to replace the entire unit.

How to troubleshoot: Before you make such a big decision, do a capacitor test. The capacitor is the part in your AC unit that starts the motor. You can test it with a multimeter.

6. Clogged Condensate Line

Remember when we mentioned the drip pan and water being drained out of your home? That water comes out of your house through a condensate line. Since it’s an enclosed, wet space, it’s a prime location for mold and mildew growth. If not flushed regularly, it can become clogged and cause your air conditioner to malfunction.

How to troubleshoot. The first thing to do is mind your safety: Do this by turning off the AC, both from the thermostat and the breaker panel. Then walk outside and locate the PVC pipe located close to the condenser unit (the outside portion of your air conditioner). Remove the cap from the top and slowly pour in one cup of distilled white vinegar. Let it sit for half an hour then flush it with water. Repeat this process once a month.

7. Unplugged Condenser Unit

Whether by accidentally unplugging it when mowing the lawn or a raccoon was feeling feisty, it’s possible for your condenser unit to become unplugged.

How to troubleshoot. Make sure it’s plugged in properly.

8. Fan Motor Stopped Working

The fan motor is located inside the condenser unit. When an air conditioner doesn’t get regular maintenance or if it’s nearing 15 to 20 years of age, it may malfunction.

How to troubleshoot. Turn off the power source to your AC. Walk outside towards the condenser unit. Unscrew the side panel and check the fan motor by doing a continuity test. Here’s a video tutorial.

9. Refrigerant Leak

The refrigerant is the gas that cools the air within your AC unit. It does its job well however, it can be poisonous if it leaks out of your AC system.

How to troubleshoot. This is the type of issue that requires a professional. In fact, federal regulations restrict the sale of refrigerant to certified HVAC technicians. To determine whether this is the problem with your AC, look at the condenser unit to see if there’s any frost on the coils. If so, you likely have a leak. Other signs are a hissing sound or an AC that turns on but doesn’t cool.

10. Your AC is Dead and Needs to be Replaced

If your air conditioner is between 15 and 20 years old, it may have run its course.

How to troubleshoot. Contact an HVAC professional to find out if the issue can be fixed or if it’s time to bite the bullet and purchase a new system.

AC Doesn’t Turn On? Contact A+ Air Conditioning in Gainesville for AC Service Repair

No matter the issue with your air conditioner, we can help you. And because we understand that a working air conditioner is essential in Florida, we offer 24/7 AC emergency service.

Call us at (352) 374-4988, and let us get your AC back to proper working order.