Why Is My Air Conditioner Not Turning On?


Even the best air conditioners can have problems. Waiting for a professional to come and fix the air conditioner is not the ideal option for anyone. Luckily, our troubleshooting guide can help you identify some common air conditioner problems. There is a difference between your air conditioner not working and not cooling. We'll help you sort both out, with the goal of getting your air conditioner pumping steady, cool air quickly.

Why Is My Air Conditioner Not Working? Here are the Top 10 Possible Issues

Regardless of what type of system you have (central, mini-split, ductless, or heat pump), there are commonalities between the types of air conditioners covered in our troubleshooting guide. If your air conditioner just won't turn on, we recommend checking a few things before calling an HVAC professional:

  • Make sure the external circuit breaker fuse is in the correct position
  • Check your electrical panel for a tripped circuit breaker
  • Check if your thermostat is on
  • Check if the air filter is clogged
  • Check if your condensate pump is working properly

Once you've checked them and everything is fine, read on for more solutions to AC problems.

Why Is My Air Conditioner Not Cooling the House?

Uneven temperatures throughout the home are not uncommon. If you notice different room temperatures or higher energy costs, there are some common causes with simple solutions.

Your Thermostat is Not Set Properly

The easiest way is to check your thermostat setting. If your thermostat is set incorrectly, your air conditioner will not work. Make sure it's not set to heat or the temperature isn't too high.

Your Air Filter is Dirty

A dirty air filter can restrict airflow and cause many problems. A short cycle turns your air conditioner on and off in very short bursts without completing a full cooling cycle. When the filters are clogged, your air conditioner has to work harder, resulting in higher energy bills and uneven cooling of your home. It can even cause your air conditioner to turn off. By regularly cleaning or replacing your air filter, you can prevent future problems or save money and stress on routine maintenance.

Blocked Vents are Reducing Air Flow

Clogged air vents are another reason your air conditioner isn't producing enough cold air. Check your vents to make sure there isn't a build-up of dirt or dust that could block airflow. Toys, furniture or closed shutters can also be the cause of the problem. Arrange furniture away from registers and check for obstacles that have accidentally fallen into your plumbing.

Why Is My Air Conditioner Fan Not Working?

If your AC unit's fan has stopped working, it could be because your circuit breaker has tripped, or something more complex. If your air conditioning fan isn't working, your HVAC system isn't cooling your home.

Burnt Out Condenser Fan Motor

An air conditioner fan motor is a fairly simple part, but if it's not working, your house won't be cool. Since the fan works hard, it is subject to heavy wear and tear, which can lead to engine damage. Fans that spin intermittently, fan blades that spin slowly, or a fan that won't spin can be a sign that the motor has a problem. This is when you need to call an HVAC technician. You can prevent AC fan motor burns by performing regular maintenance and reducing dirt and dust in and around your system.

Capacitor is Failing

No, the capacitor is not a time-traveling device. Start and run capacitors are devices that send power to the fan motor and power the air conditioner when power is needed. These small but mighty workhorses keep your system running smoothly so your air conditioner doesn't suddenly switch off. When this happens, you may hear a humming noise from your air conditioner without actually starting it - it's your starting capacitor telling you it's time to call an HVAC professional. If your system is cycling short, randomly shutting down, or AC lag, your run capacitor may be failing. You cannot fix this yourself either. Call an HVAC technician for help.

Condensate Pump is Failing

Checking the condensate pump is a fairly easy DIY test. Condensate pumps typically have shorter lifespans than air conditioners and furnaces as they run for both cooling and heating (depending on furnace efficiency). These pumps usually have a test button. Make sure there is some water in the basin and press the test button to ensure it pumps the water out. A failing or failed condensate pump will often trip the furnace so that it won’t run and create a pool of water wherever the furnace is (eg. basement or worse, the attic).

Why Is My Air Conditioner Making Noise?

Air conditioners, when they are functioning optimally, are pretty quiet. There can be the occasional noise when they complete a cycle but if they suddenly start squealing, hissing, buzzing, rattling, clicking, or banging – you get the picture – then it is time to do some investigation. Rattling or banging could mean something has come loose, while buzzing often means you have an electrical issue. Any kind of persistent noise is a cry for help from your air conditioning unit. Turn off your AC and call an HVAC professional to come out and assess your system for issues. 

Why Is My Air Conditioner Not Turning Off?

The opposite of your air conditioner not coming on – not turning off – is also a sign of a problem. If your air conditioner is constantly blowing it puts a huge amount of stress on your system, leading to high energy bills and a shorter life span. Beyond checking your thermostat that it is at a realistic temperature, a couple of other things could be the cause. 

Frozen Evaporator Coil

This could be a sign that you have a refrigerant leak somewhere. Because your AC system can’t get the temperature of your home to ideal it will keep running indefinitely. This is something that needs to be dealt with immediately. Turn off your system and call an AC repair consultant right away. 

Dirt on the Condenser Coil

Yep. That pesky dirt can cause havoc everywhere in your system. The condenser coil’s job is to disperse heat outside your home. If dirt has built up, heat will be trapped inside the air conditioner and keep your system running to reach the target cooling temperature your thermostat is calling for. 

Can I Reset My AC?

Most professionally installed ACs will not have reset buttons. Power outages or surges, while rare in Jacksonville, Texas, can be the reason your air conditioner isn’t working, however, they will typically come back on as long as you have power. 

Still, after a power outage, it’s a good idea to check your system and your breaker box. Your circuit breaker could have been tripped for your AC or furnace, so it’s important to check both places. A key indicator is that if the thermostat is blank, the furnace might not have power.

Try turning your AC off at the thermostat and resetting your circuit breaker. Wait a half an hour before turning it back on. If you are still having difficulties it’s time to call in the professionals before it becomes a worse problem. 

When to Call an HVAC Professional

Safety is always the first priority. When you have hit a wall in your troubleshooting measures it is time to contact a professional. Trying to “limp along” is just potentially causing more damage to your system that will increase ac repair costs. If in doubt, turn off your system and contact Bannister Plumbing & Air for help. 

How Bannister Plumbing & Air Can Help

If you are looking for help troubleshooting your air conditioning system, our consultants at Bannister Plumbing & Air can examine your system and determine what repairs need to be made. If you need air conditioning maintenance we are ready to help you save money and keep surprise breakdowns away. You can schedule your next tune-up and keep the stress and hassle out of maintaining your system. No matter what you need we’re always just a phone call away.