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7 Reasons Why Your AC Is Running But Not Cooling

Keeping cool in the summer heat is always a top priority. However, there can be times when you notice that your AC is running, but it’s not cooling your home as effectively as it should. This can be both perplexing and frustrating, especially during a heatwave. There are a number of potential reasons for this issue, ranging from simple fixes to more complex mechanical problems.

Here are seven common reasons why your AC might be running but not cooling.

1. Dirty Filters

A common reason your air conditioning unit may not be cooling is due to dirty filters. Pollen, dust, pet dander, and other particles can accumulate on your filter and obstruct airflow. Your system will continue to run but with significantly decreased cooling capability.

Changing or cleaning your filters regularly can take care of this problem. If your AC unit is still not cooling after the filters are clean, the issue may lie elsewhere. It’s also important to note that chronic neglect of filter changes can lead to more serious problems.

2. Low Refrigerant Levels

The refrigerant is the substance that your air conditioner uses to remove heat from the air inside your house. If the levels of the refrigerant are low, the AC will not cool effectively. This often results from leaks in the refrigerant lines, which are not always immediately apparent.

However, getting someone to simply refill the refrigerant isn’t a long-term solution, as the leak will continue to cause the level to drop over time. It’s essential to call in a professional to locate and repair the leaks, then recharge the refrigerant to the appropriate levels.

3. Faulty Thermostat Settings

Your thermostat controls the operation of your AC unit. If it’s set incorrectly or is malfunctioning, it may cause your AC to run without cooling. For example, the fan setting can make the AC run without activating the cooling cycle, giving the illusion of an operational but ineffective system.

First, check your thermostat settings. If everything seems in order, but the problem persists, you might be dealing with a faulty thermostat that needs repair or replacement. Modern smart thermostats can offer additional troubleshooting support through error codes and system health checks.

4. Condenser Unit Issues

The condenser unit of your AC, typically located outside, is responsible for expelling the collected heat from your house to the outdoors. If it’s dirty or blocked by debris, it can greatly impact your AC’s ability to cool.

Regularly clean and check the condenser unit to ensure there’s nothing obstructing its function. Be aware that problems can also stem from internal parts of the unit, such as the condenser coils or fan motor. These issues usually require professional attention.

5. Air Duct Leaks or Obstructions

Your AC system’s ductwork carries cooled air from the unit into the rooms of your house. Any leaks or obstructions in these ducts can result in cool air not reaching its intended destination, making your AC seem like it’s not cooling.

Inspect your ductwork for visible signs of damage or blockages, and ensure all vents are open and unblocked. For more hidden duct issues, consider hiring a professional to perform a duct leakage test and necessary repairs.

6. Damaged or Worn-out Compressor

The compressor is the heart of your AC system, pressurizing the refrigerant to facilitate the cooling process. A damaged or worn-out compressor can result in the AC running but not cooling.

If you suspect a compressor issue, you’ll need to seek professional help. Compressor problems often require technical expertise to diagnose and fix, and in some cases, the compressor may need to be replaced entirely.

7. Incorrectly Sized AC Unit

An AC unit that’s too small for the space it’s intended to cool will struggle to maintain the desired temperature. Similarly, an oversized unit will cycle on and off too frequently, impacting its ability to dehumidify the air effectively and making the space feel less comfortable.

If you’ve ruled out other potential issues and your AC is still not cooling, it might be worth consulting with a professional to see if your AC unit is the right size for your home. Upgrading or downgrading to a more suitable unit could ultimately save you money and provide a more comfortable indoor environment.

Contact HVAC Professionals to Learn More

Dugan Air specializes in heating and cooling services for customers in Franklin and the surrounding areas. We also provide new construction installations, maintenance programs, emergency services, and much more. Reach out to Duga Air today to learn more about using our services.



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