10 Common Causes of Air Conditioner Breakdowns

Air conditioners are large investments and are critical to keeping your home or business cool during the hot summer months. Southern AC and Heating has done many ac repairs and we’ve created a list of the most common reasons your air conditioner might break down, and how to avoid these issues. If you have any AC repair needs give us a call at (985) 498-2576.

Dirty HVAC Filter

What happens when HVAC filter is dirty?

To keep your air conditioner running at peak efficiency, you should clean the filters regularly. Dirty filters force the air conditioner to work harder to keep the house cool. This will result in more frequent AC repairs and, eventually, shorten the unit’s lifespan.

What happens if you don’t clean your AC filter?

Dirty filters restrict the flow of cold air which can cause it to build up inside the air conditioner. The final result could be the formation of ice on the coils. If you notice any of these symptoms it’s a good idea to schedule service on the air conditioner right away.

Your unit is running because it’s hotter or colder outside than usual
Air filters need to be cleaned or replaced periodically in order for them to work as efficiently as possible. When it’s hot or cold outside, it’s important that you replace your air filters because your ac unit will be running regularly throughout the day and night. This will cause the filter to become dirty faster.

How often should air filters be changed?

You should have an air filter change every 90 days in your vacation house or if you have one or more pets and no allergies. You should change your air filter in your ordinary suburban home every 6–12 months. And, if you have one dog or cat, you should change your air filter at least every 60 days. Air filters are very cheap and can be found in most big box store like Walmart or Target.

Thermostat Malfunction

What happens when AC thermostat goes bad?

Typically your ac unit will not turn on, if this is the case you should immediately call a professional if your HVAC system won’t turn on. The most obvious sign that something is wrong is that the HVAC system won’t turn on or respond to the thermostat.

Signs You Need a New Thermostat

Your heating or cooling system is not working properly. The temperature gauge is incorrect. You’ve been experiencing frequent temperature fluctuations. The thermostat is 10 years old or older.

Malfunctioning AC Thermostat

Evaporator Coil Issues

How does evaporator coil go bad?

Erosion is the main cause for an evaporator coil to go bad. Over time, the evaporator’s coils will erode or wear down due to the refrigerant flowing through them. Even some evaporator cleaning solutions or products can corrode or weaken the outer lining of the coil.

Can evaporator coil leak be fixed?

Unfortunately, repairing an evaporator coil isn’t a feasible option. There is no reliable or consistent technique or products to use for repairing evaporator coils. We recommend scheduling an ac repair appointment with a local HVAC contractor. We do not recommend doing refrigerant repairs if you are not a certified technician. Refrigerant can be dangerous and should only be handled and check by a trained professional.

When should an evaporator coil be replaced?

The average lifetime of an AC is approximately 10 to 15 years. After 15 years, your AC unit will break down more often. If you just serviced your unit a few months ago and something broke afterward, it may be time to replace it. Some coil cleaners can also weaken and disintegrate the outer lining of evaporator coils.
Most air conditioning systems last about 10 to 15 years on average. In our experience after 15 years your ac unit will begin to breakdown at an increasingly higher rate. To prevent your AC system from breaking down it should be serviced at least once a year, or even one per quarter, to ensure the best possible air conditioning performance.

Residential AC Evaporator Coil Replacement Cost

The typical cost for replacing an air conditioner’s evaporator coil is about $1,000. It ranges from $600 to $2,000, and it usually includes a 40% labor cost of $400 to $1,000, typically manufacturer’s warranty, and this estimate usually covers the price of the materials.

AC Damaged Coils

Dirty AC Condenser Coils

If a condenser coil is dirty or fouled, its ability to reject heat is severely affected. Remember, the main function of the condenser is to condense the refrigerant vapor to liquid. Condensing is system dependent and usually takes place in the lower two-thirds of the condenser.

If your ac’s condenser coil gets excessively dirty or damaged, it lowers its ability to reject heat. Remember that the condenser coil’s primary function is to condense the refrigerant vapor to liquid. That usually happens in the lower two-thirds of the condenser.

How do I know if my AC condenser is clogged?

  • The unit is making abnormal or loud noises 
  • The cooling capacity of the unit has decreased significantly 
  • Your AC unit is leaking more than the typical amount of fluid for condensation


What happens if your condenser coil is dirty?

A dirty condenser coil with have a reduced ability to transfer heat to the outside air and this can lead to a less effective cooling system. Dirty condenser coils forces the unit to work harder, which leads to more wear and tear on the system.

Dirty condenser coils reduce the unit’s ability to transfer heat to the outside air and this can lead to a less effective cooling system. Dirty condenser coils requires the unit to work harder, which causes it to wear out faster, and thus increases the chances of having to repair it.

How much does it cost to clean condenser coils?

Get an AC tuneup as soon as your season begins. It’ll cost $100 to $400 to clean your AC coils. A condenser coil cleaning service will happen during your annual AC tuneup, and it costs $75 to $200.

damaged air conditioner coils

Refrigerant Leaks

What happens if AC refrigerant leaks?

Losing refrigerant can make your system cool inefficiently. If your air conditioning system fails to produce enough cold air, you could experience a loss in comfort. As a result, your AC may work harder than necessary, increasing your monthly energy bills.

How much does it cost to fix an AC refrigerant leak?

Freon leak repair costs on average somewhere between $200 and $1,000. The price is determined by how much or corrosion or holes there are in the coils where the refrigerant lives, and where leaks occur. If your refrigerant level is low your ac will have a difficult time cooling your home or business.

How common are refrigerant leaks?

Air conditioner refrigerant leaks are somewhat common but can be difficult to diagnose if you’re not a professional. Coolant leaks affect the HVAC system significantly and can cause utility bill increases along with repair issues down the road.

Can a refrigerant leak be fixed?

It is possible to fix or replace a leaking refrigerant line. If refrigerant line is replaced the refrigerant will need to be replaced or recovered as well.

ac refrigerant leak

Bad Capacitor

The AC capacitor stores electrons to provide the air conditioning unit start up energy, the capacitor builds up an electrical charge for that start up energy.

How do I know if my air conditioner capacitor is bad?

Common Symptoms of a bad AC Capacitor:


  • Air conditioner is not producing cold air
  • The air conditioner takes a long time to start once it has been turned on
  • You hear abnormal humming sounds coming from the air conditioner
  • The air conditioner is turning off before your home is cool
  • Your air conditioner unit will not turn on


The most common problem that bad capacitors can cause is “hard starting.” This is when the compressor of an AC has difficulty starting up, stutters trying to turn on, and then shuts off a short while later.

If your compressor isn’t starting, or if it starts and stops, then there’s a chance your compressor may have a problem with its capacitors. When the compressor first turns on, the current surges from nothing to full speed. That surge causes voltage spikes in the electrical system. A common problem is “hard starting” which is where the ac compressor has trouble starting, stutters attempting to turn on, then turns off.

Can I run my AC with a bad capacitor?

If your capacitor has failed, wait for the repair person to come and fix it. Doing so could cause more damage, which will cost you more money and take you longer to get your system back up and running.

What causes AC capacitor failure?

  • Debris damage to the capacitor or other physical damage to the capacitor can cause problems.
  • The incorrect amount of current or voltage traveling going through the capacitor.
  • Improper voltage or current traveling through the capacitor.
  • The unit overheating
  • Age related wear and tear.


What To Do When the Capacitor Breaks Down
Call a qualified AC Repair company like Southern AC and Heating.

AC Capacitor

Inadequate Maintenance

What happens if you don’t service your air conditioner?

A neglected heating and air conditioning system can result in a costly repair bill, a system that doesn’t perform efficiently, and a system that will most likely need to be replaced before its anticipated lifespan has passed.

How Often Is AC Service Needed?

Air conditioners usually need to be serviced twice yearly, once in the fall and once in the spring. They’re fairly reliable, but if you take good care of yours, it should last you many years.
This is to ensure that it’s clean, that its parts are in good shape and that it’s operating as optimally as possible.

Proper AC Maintenance

Frozen Coil

Two of the most common signs that your ac has a frozen coil is that your ac unit isn’t blowing cool air and there is visible ice on any part of the HVAC system. If your ac is on and is blowing hot air you probably have ice forming somewhere on the system itself. Another common sign is a hissing noise coming from the ac.

The most common reason for a frozen ac coil is a dirty air filter. The air which is circulated throughout your home is filtered by the ac filter. The more your air conditioner runs, especially summer months, your filter will catch dirt, debris, allergens, and more. As the filter gets dirtier and dirtier the air has a more difficult time passing through the filter leading to your HVAC coils freezing.

Frozen AC Condensor Coils

Outside Fan is Broken

Why is my AC outside unit fan not turning on?

If your outside ac unit’s fan is not turning on when your ac unit is working, you may have a bad fan motor. first check for debris wrapped around the fan axle, another common issue is the motor bearings being jammed or dirty to the point of your fan not working.

How much does it cost to replace an AC fan motor?

The average price to replace a fan is around $300 – $600 depending on the brand and availability. Having a working fan is extremely important, as running the ac without one will put stress on the ac’s compressor thus risking damage to the compressor as well. Compressor repairs are more financially large — usually costing close to $2,000.

broken ac fan


If you are in the Southeast Louisiana and are having trouble with any of the items on this list, give Southern AC and Heating a call. We are trained and certified ac professionals and will get your problem fixed as soon as possible.

Southern AC and Heating
904 Fig St Morgan City, LA 70380
(985) 498-2576

Leave a Comment

Your email address will not be published. Required fields are marked *

Call Now for Appointment