How much does it cost to repair a central air conditioner?

Reviewed by Adam Graham remodeling expert. Written by Fixr.com.

Central air conditioners can be found in many homes, helping control the temperature throughout the property. They are a convenient and low-maintenance option for homeowners to keep their homes cool in summer. However, a range of issues can arise with central air systems, from leaks and clogged filters to broken ductwork and mold infestations.

The national average cost for central air repairs is between $100 and $500, with most homeowners spending around $300 to replace a broken thermostat. This project’s low cost is $75 to change a dirty filter. The high cost is $6,000 to replace extensive sections of ductwork.

Cost to Repair Central Air

Central Air Repair Cost by Type of Repair

Central air systems are complicated with many components that may break and require repairs. The cost of repairs depends on the problem because some issues are simpler and cheaper to fix than others. The table below shows common problems and the average repair costs for each.

Repair a Central AC Thermostat

The average cost of central air thermostat repairs is between $100 and $300. The thermostat is one of the most important parts of the system because it helps control the air temperature. A faulty thermostat can cause the system to stop working correctly. An HVAC technician may need to clean the thermostat or reboot the system to get it working again.

Central AC Coil Repair

Homeowners pay between $200 and $475 for central AC coil repairs. AC units typically contain evaporator and condenser coils, and both can break and need to be repaired. A common issue is that the coils get dirty and may not run as efficiently, so they must be cleaned by a professional.

Air Duct Repair

Homeowners spend between $200 and $800 on air duct repairs. However, prices can be significantly higher if you live in a large house with seriously damaged or moldy ductwork. Ducts usually only require basic repairs, such as patching cracks, hammering dents, or sealing leaky sections to prevent future leaks.

Central Air Blower Motor Repair

The average cost for central air blower motor repairs ranges from $300 to $600. The blower motor is responsible for powering the fan in your central AC system, which blows the air through the ducts and allows it to circulate. If it stops working, you may find that the entire system does not run as efficiently. An HVAC technician may be able to make adjustments and rewire a faulty motor to get it running again.

Central Air Compressor Repair

The cost of central air compressor repairs averages $600 to $1,200. The compressor is a key part of the system because it helps provide the pressure necessary for refrigerants to flow and work. You may notice compressor issues if the air flowing out of the vents is not cold. A repairman can make repairs to a damaged compressor, such as adjusting valves or replacing the floating seal.

Central Air Conditioner Repair Cost by Type of Replacement

In some situations, parts of your central air conditioner system may be too damaged to be repaired. The broken parts must be replaced in this case. The cost of this varies greatly because some parts are inexpensive to buy and easy to install, but others are more expensive or difficult to install, requiring extra hours of labor. The table below shows average costs to replace various central AC parts, including parts and labor.

Replace Fuses in a Central Air Conditioning Unit

To replace a central air fuse, expect to pay between $50 and $150. Fuses for AC systems work like fuses for other appliances and devices. They can blow when overloaded. When this happens, you need to fit a new fuse. Luckily, new fuses are usually cheap and can be installed in minutes.

Filter Replacement

Homeowners pay between $75 and $150 for filter replacements in these systems. This is one of the simplest and cheapest repairs, and you can save money by doing it yourself. However, if you want to get a professional to do it for you, they charge a standard fee. Filters need to be replaced when they become excessively dirty. Otherwise, the system does not function as well and air cannot flow cleanly through the ducts.

Central AC Capacitor Replacement

To replace a central air capacitor, expect to pay between $150 and $400. The capacitor of the AC system stores energy to boost the system at the start of each new cycle like a battery. Wiring issues and other problems can cause capacitors to fail, which must be replaced.

Central Air Thermostat Replacement

The average cost to have a central air thermostat replaced is between $150 and $500. The price depends on the thermostat type needed because some brands use more advanced and expensive thermostats. You usually need a new thermostat if your system stops cooling correctly.

Central Air Contactor Replacement

Replacing a central air contactor ranges from $175 to $400. The contactor works with the capacitor to keep power flowing to the system. If it breaks, you may notice a strange "chattering" sound coming from the system, especially around the condenser.

Circuit Breaker Replacement

The average cost to replace a central air circuit breaker is between $200 and $600. If the circuit board is broken, your AC system may not turn on at all because the various components are not getting energy. If this happens, the entire circuit board may need to be replaced.

Central Air Fan Motor Replacement

Replacing a central air fan motor costs between $400 and $750. The motor is responsible for powering the fan that blows air through the home, so if it breaks, you may notice air is not flowing and the home is slow to cool. You may also hear lots of noise if your fan is not working correctly.

Evaporator Coil Replacement

The cost to have an evaporator coil replaced averages $600 to $2,000. The evaporator coil helps take heat from the inside to the outside. The coil may be broken if your home is not cooling down properly, and it could cause other issues if left unattended, such as refrigerant leaks.

Central Air Condenser Replacement

Homeowners spend between $800 and $2,000 on condenser replacements. The condenser is positioned outside and used with the compressor to convert the refrigerant from gas to liquid. It can get damaged from exposure to the elements and outside factors.

Central AC Compressor Repair

The average cost to have a central air compressor replaced ranges from $1,000 to $2,500. Some of the signs that may appear when your central AC system has a broken compressor include hot air coming from the vents and the system failing to cool your home. You might also notice loud sounds coming from the system.

Replace HVAC Ductwork

Homeowners pay between $3,000 and $6,000 for ductwork replacements in central air systems. The total price depends on how much ductwork needs replacing. Signs that ducts need replacing include increasing energy bills, rooms that feel warm or cold, and rooms that look dusty.

Central Air Conditioner Repair Cost by Problem

Many problems can arise with your central air conditioner system, from water leaks to strange sounds, clogs, holes, and dirty ducts. The repair cost and procedure vary for each problem, with some issues being simple and inexpensive to fix and others requiring more work, time, and effort. The table below shows average total repair costs for a range of common AC problems.

Central AC Short Cycling

Homeowners spend between $75 and $600 to deal with short cycling issues in their central AC systems. Short cycling is when the air conditioner starts but runs for a short period, like a few seconds, before turning off. It then repeats the process over and over. This can be frustrating to deal with, and it may be caused by different issues, such as clogged filters, a lack of refrigerant, or problems with the circuit breaker.

Clogged Central Air Drain Line

To fix a clogged drain line in a central air system, expect to spend $100 to $200. Drain lines from central air systems can get clogged by dirt, debris, and even leaves that fall into the system. If left unattended, these blockages can grow bigger and more problematic, eventually causing unpleasant smells and standing water.

Dirt and Debris

The average cost to deal with dirt and debris in a central air system ranges from $100 to $250. Dirt, dust, and debris can accumulate in central air systems. The system must be carefully cleaned to deal with this problem. A new filter might also be needed to catch dirt and dust and prevent further problems.

Leaking Water

Homeowners spend between $150 and $500 to fix a central air system that is leaking water. You may need to pay extra for emergency repair services on serious water leaks. Usually, when a central air system is leaking water, it is caused by issues like clogged drain lines, dirty filters, or a lack of refrigerant. The system may need cleaning or could require a recharge of Freon.

Central AC Not Blowing Cold Air

The average cost to repair a central air system that is not blowing cold air is between $150 and $800. There could be several possible explanations when a central AC is failing to blow cold air. It could be that the filters are clogged and obstructing the flow of air or an issue with a lack of refrigerant or something with the coils.

Hole in a Central AC Duct

The cost to repair a hole in a central air system averages $200 to $800. The price depends on the hole size and if the problem can be repaired or the damaged duct needs to be replaced. Small holes can be patched, but for bigger holes, the damaged duct may need to be removed and replaced.

Unit Freezing Up

Homeowners spend between $200 and $2,000 to fix a central air system that freezes. The unit freezing is often caused by a problem with the evaporator coil. The evaporator coil must be repaired or replaced, with replacements costing more than repairs.

Making Noise

If your central air system makes lots of noise, expect to spend between $200 and $2,500 to fix it. The reason for this wide price range is there are several possible reasons why your central AC might be making noise, and some are cheaper to fix than others. The system might be running low on refrigerant or have a broken compressor. You need to call an HVAC technician to figure out the problem and decide how to fix it.

Central AC Weak Airflow

If your central air system has weak airflow, expect to pay between $300 and $750 for repairs. When you notice weak airflow in your central AC system, it usually means that the fan is not working or the motor powering the fan has broken. You may require a new fan or motor or repairs to these components.

Repair a Freon Leak in Central Air

The average cost to repair a Freon leak in a central air system ranges from $400 to $1,000. Freon is the name of the refrigerant commonly used in central air conditioning systems. Freon may leak from damages in the system, causing the system to become less efficient or even stop working. An HVAC technician can find the leak, repair the damage, and refill your system with more Freon to solve the problem.

Central Air Conditioner Smells Musty

If your central air system smells musty, expect to spend between $400 and $2,000 to fix it. A musty smell is a sign that bacteria are growing inside your AC system, potentially in the drain line or on the evaporator coil. The system needs to be cleaned and certain components may need repairing like the coils. In the worst cases, you may even need some of the ductwork replaced, raising costs.

Labor Cost to Repair a Central AC Unit

Central air repair workers charge between $65 and $150 per hour for their services. You may have to pay a high labor fee for this repair work because central air systems can be very complex and often require specialist technical repairs from highly trained certified professionals. Many HVAC technicians charge a call-out fee of around $75 to $150 but may waive this if you hire them after they have inspected your system. Some repair workers may charge extra if you live in a remote location and they have to travel far to your home. You may also find that some repair companies have set fees for jobs like changing a filter or fixing a thermostat.

Emergency Central Air Repair Cost

Expect to pay an extra $100 to $250 for emergency central air repairs. HVAC technicians usually charge extra for urgent or same-day repairs because they may need to delay other appointments and reorganize their schedules to accommodate your repairs. Emergency central air repairs may be needed in situations when the central air system has completely failed or is leaking and could seriously damage your home.

Central AC Maintenance

The average annual cost for central AC maintenance is between $85 and $150. This cost covers a yearly service check for your central air system. During this check, an HVAC technician inspects the system, including ducts, motors, fans, and filters, looking for signs of damage or other issues. They usually clean or replace the filter and clean surface dust and debris. They may also add new refrigerant to the system, carry out other simple maintenance tasks, and provide a full report of everything they found and did. The best time to do this maintenance is before you plan on using your central air system the most. For most people, this is during the spring, before summer starts.

Recharge Central Air

It costs around $200 to $500 to recharge the Freon in a central air system. The total cost depends on your system’s size and how much Freon is required. You need to have the system recharged and checked for leaks if you notice signs of low Freon levels, such as rooms not cooling, hissing sounds in the refrigerant line, or higher-than-average energy bills. You may also spot ice appearing on the refrigerant line. If any of these signs appear, your system is likely low on Freon and needs checking. An HVAC technician can check for Freon leaks during a standard maintenance service, which is best carried out in the spring each year.

Repair vs Replace a Central AC Unit

In some situations, you may hesitate between having your central AC unit repaired or replaced. It can be difficult to make this decision, and it is important to consider several factors to help decide on the right option. It is also recommended to call an HVAC technician out to your home so that they can inspect the central air system, find out what is wrong with it, and give you their professional opinion on whether to repair or replace.

In general, the main thing to think about when it comes to repairing or replacing a central AC unit is the cost. The average cost to install a new central AC is between $5,000 and $12,000. Therefore, the cost of replacement is significantly higher than most typical repair jobs. However, you also need to think about long-term value. If you keep your old central air system and it continues to break, you may need to pay recurring repair costs every year, leading to more lost money in the long run compared to replacing the system.

HVAC technicians often recommend homeowners to apply the “$5,000 rule.” To use this rule, multiply the estimated cost of repairs by the age of your AC system in years. If the value you end up with is lower than $5,000, it is best to repair the system. If the final total is higher than $5,000, replacement is the better option. For example, if your repairs will cost $500 and the system is 7 years old, multiply $500 by 7, giving you a total of $3,500. This is less than $5,000, so you should repair the unit. If your repairs are priced at $1,000, multiply $1,000 by 7 for a total of $7,000, which is more than $5,000, so the system should be replaced.

Enhancement and Improvement Costs

Outside AC Unit Repair

Homeowners pay an average of $200 to $700 for repairs to an outside AC unit. Outdoor AC units must be strong and sturdy to withstand damages from the weather and changing exterior temperatures. It is also normal for them to wear and develop issues like cracks, holes, and other damages. They may need to be cleaned, patched, or have parts replaced.

Cleaning Central Air Unit

The average cost to have a central air unit cleaned is between $100 and $250. The cost depends on the system size and the amount of cleaning required. You should request some minor cleaning as part of a routine maintenance check for your system, but the central air unit may require a deeper clean if dirt and dust are present.

Additional Considerations and Costs

• Troubleshooting. Homeowners can take a few steps to troubleshoot minor central AC issues like checking the filter, thermostat settings, and vents.
• Reset. Another step you can take as a homeowner to deal with certain central AC issues is to reset the system. Turn the thermostat off and turn the AC off with the power switch or via the circuit break. Wait 60 seconds and turn it all back on.
• Warranty. Typically, a central air unit should come with some warranty, which may last for one or more years. If your system was recently installed, check the warranty policy to see if you can make a claim.
• DIY. There are some basic central air maintenance tasks you can do yourself like cleaning and changing the filter or cleaning dust and dirt from the vents and ducts. However, it is best to contact the professionals for more serious issues.
• Insurance. Your homeowners insurance policy may cover certain damages and problems to your home’s central AC system and ductwork, but other issues may not be covered. Check the fine print to learn more.
• Lifespan. On average, a central AC system can last from 15 to 20 years before it starts breaking down regularly and needs replacement.
• License. Central air systems are complicated and must be worked on by proper professionals. Ensure you hire a licensed HVAC contractor or repair specialist to deal with central AC repairs.