ABC Blog

My AC Is Not Turning On: What’s Wrong

An AC vent that won't turn on

For a homeowner, there are few things as distressing as turning on your air conditioner and nothing happening. This holds especially true when the temperatures start climbing to triple digits. Fortunately, there are a few things that you can check yourself to get that cool air flowing again.

Some Easier Fixes

Let’s start with the basics. Your air conditioner might not be getting any juice. Take a look at your breaker box and see if there is a tripped fuse or a breaker has blown. Those are easy fixes that might get your system up and running.

Ductwork Issues

On the system’s outside unit, you have a condenser that takes the warmer air from your home, cools it and sends it back through your home’s air ducts. It is possible that rodents have chewed through the cord that links your outdoor unit to your home’s electrical system. If rodents are your problem, you may experience additional issues as well, such as damaged insulation.

This is not a simple repair and is better handled by a licensed air conditioning system expert. They have the know-how to efficiently handle all types of problems with air conditioning and take the worry out of the entire system.

Clogged Filter

The filter inside your air conditioner needs to be changed regularly to keep your system functioning correctly. In general, it is a good idea to change out the filter every one to three months. Homes that house pets may need a filter switch every four weeks or so.

Filters collect all kinds of dust and debris and if it becomes dirty enough, your unit will have to work even harder to cool the house. Eventually, it can ice over and stop cooling entirely.

To unfreeze an evaporator, first, turn off your system and the breaker that supplies it with electricity. Then change the filter. Once you have completed these steps, allow the evaporator to de-ice. Also, take a look at your condenser. If they have a lot of gunk build-up, clean them as well. Again, if you don’t feel confident doing this yourself, a licensed air conditioning expert can perform the task for you. In fact, they can perform other tasks such as changing the air filter in your home and cleaning your drain line.

Motor Failure

Your air conditioning system might have a failed capacitor, which is what runs your whole system. If your outdoor unit is 15 to 20 years old, there is a good chance it needs replacing. You can use a multimeter, but if the device shows no power, replacing the motor is a job for a licensed pro. An expert will get your system up and running quickly, plus tell you of any other issues you might have with it.

A house where the ac keeps turning off

Why Does My AC Keep Turning Off?

When your unit runs for a short time and then turns off without reaching the set temperature on the thermostat, it is short cycling. This isn’t just uncomfortable; it can raise your electric bills and keep your unit from performing effectively. That can damage the system’s components.

Continuing Breaker and Fuse Issues

Say you see a blown fuse or tripped breaker when you can’t get the air conditioning system up and running. If you have to change the fuses often or the breaker keeps turning off, that can signal a bigger problem.

If you notice the lights on other appliances flickering or turning off, it could signal that you are using too much electricity for your home’s capacity. This can also affect the air conditioning system’s function. To combat this, consider reducing the number of appliances you run at the same time. If your home is older, your electric system might have other issues as well.

Undersized Unit

The capacity of your home’s cooling system might be too small for the size of your home. If you have a larger home with two floors, you might need to install two outside units to handle the load. Again, a licensed air conditioning system professional will be able to calculate whether this is the problem and recommend other units that would be more appropriate for your home’s size.

It might seem to go against the above thinking, but using an oversized unit is also another AC problem that can cause the system to turn off prematurely. A too-big system cools too quickly and will turn off often. A consultation with a licensed professional will help here as well.

Leaking Refrigerant

When bills go up more than usual or you hear a hissing noise near the outside unit, the likely cause is a refrigerant leak. This will eventually cause the evaporator coils to freeze on the unit with a block of ice over it, even in the warmer air.

This isn’t something you can handle on your own. The Environmental Protection Agency has determined that only a licensed technician can take care of refrigerant issues, it’s important to call them in as soon as you notice it.

Faulty Parts

Your system uses a run capacitor to provide the electrical boost that keeps the air conditioner functioning correctly. In that same vein, other parts of the electrical system in the unit can cause short cycling as well.

Improper Thermostat Placement

If the device is in a place that gets warm quickly, near an air vent or window or on a side of your home that gets a lot of shade, it won’t cool the house correctly. This mismatch between your set temperature and the efficiency of the air conditioning system will make for uneven temperatures and short cycling.

My Thermostat is Blank and the AC Isn’t Working

Your thermometer is what “talks” to your air conditioner and lets it know it needs to start pumping out cold air. If your thermostat is not working and neither the breaker or fuse is the problem, take a look at the screen, if your thermostat has one. Many people don’t realize that some thermostats need batteries to function correctly.

An improperly calibrated thermostat will also keep the air conditioner from kicking on. Despite newer technology that has improved thermostats, the newer, digital units may still need adjustments. If this is something you would rather not tackle yourself, contact a licensed professional and they will be happy to take care of the AC problem.

If your air conditioning doesn’t switch on even after a battery change, or if your unit is wired to your house’s electrical system, check your interior wiring. Something as simple as a frayed wire or one that is loose could keep your air conditioner from turning on.

Once you get to this point in your investigation, if the unit still won’t turn on, thermostat replacement is a strong possibility. Contact a specialist to give your air conditioning system a full inspection and diagnose the issue.

It’s important to take care of short cycling issues as soon as you notice the system turning on and off often. Air conditioners remove humidity as well as cool the air, so if yours is turning off and on, it will start to feel sticky and uncomfortable. The issue will also cause higher electric bills and increased wear and tear on the system’s components. One of the best ways to avoid problems with your air conditioner right at the time you need it most is to call a licensed air conditioning specialist for a thorough inspection and to set up a regular maintenance schedule.

ABC Can Repair and Maintain Your AC

When your AC system isn’t working properly, it’s the best bet to contact a licensed professional for AC repair. ABC Home & Commercial Services can maintain your system and notify you of any potential problems before they become bigger headaches.

Stephen Richardson

Stephen Richardson is the HVAC Director for ABC Dallas and Fort Worth. Stephen has over 37 years of experience in the HVAC industry and has been with ABC for 21 of those years. Before joining ABC, Stephen held positions as a Building Engineer, Refrigeration Service Technician, and AC/Refrigeration Mechanic. In his off-time, he enjoys cooking, restoring vintage tractors, and SLR photography.

Learn More

Comments are closed.