Troubleshooting a Split AC Not Cooling But Fan is Running (12 Possible Reasons)

Video: Troubleshooting a Split AC Not Cooling But Fan is Running (12 Possible Reasons)

Figure 1: Split air conditioner outdoor unit.

A split air conditioner, known for its efficiency and comfort, can be a savior during the scorching summer months. However, when your split AC is running, and the fan is working tirelessly, but you still find your room uncomfortably warm, it can be quite frustrating. In this comprehensive guide, we will delve into the reasons why your split air conditioner may not be cooling while the fan is running, and we will provide practical solutions to help you beat the heat.

1. 12 Reasons and Solutions Why the Split AC is Not Cooling But Fan is Running

1.1 Low Airflow

One of the primary reasons for reduced cooling efficiency in a split AC is inadequate airflow. When the air conditioner doesn't circulate enough air through the system, it struggles to cool the room effectively.

Solution: Ensure that there are no obstructions blocking the vents or the indoor unit. Also, check that all doors and windows in the room are closed, allowing the AC to cool the space more efficiently.

Figure 2: Split air conditioner indoor unit.

1.2 Clogged Air Filter

Over time, the air filter in your split AC can become clogged with dust, dirt, and debris. This impedes the flow of air and can lead to reduced cooling performance.

Solution: Regularly clean or replace the air filter according to the manufacturer's recommendations. This simple maintenance task can significantly improve your AC's performance.

1.3 Dirty Evaporator Coil

The evaporator coil is responsible for absorbing heat from the indoor air. If it becomes dirty or covered in grime, it can't efficiently cool the air passing over it.

Solution: Schedule professional maintenance to have the evaporator coil cleaned. Avoid DIY cleaning, as it can damage the coil if not done correctly.

Figure 3: dust on split air conditioner evaporator coil

1.4 Frozen Evaporator Coil

If your evaporator coil freezes, it won't be able to absorb heat effectively, leading to reduced cooling performance.

Solution: Turn off the AC and let the fan run to defrost the coil. This can take a few hours. If the issue persists, it's advisable to call a professional technician to diagnose and resolve the underlying problem.

1.5 Incorrect Thermostat Settings

Sometimes, the issue might be as simple as incorrect thermostat settings. If the thermostat is set too high or in the heating mode, your AC will not provide cooling.

Solution: Ensure that your thermostat is set to the desired cooling mode and that the temperature setting is lower than the current room temperature.

Figure 4: Programmable thermostat.

1.6 Undersized Air Conditioner

An air conditioner that is too small for the space it's intended to cool will struggle to maintain a comfortable temperature.

Solution: If your AC is undersized, consider upgrading to a larger unit that can handle the cooling load of your room effectively.

1.7 Blocked Condenser Unit

The outdoor condenser unit plays a crucial role in releasing heat from your home's interior. Obstructions around the condenser, such as leaves, debris, or dirt, can hinder its efficiency.

Solution: Regularly clean the area around the condenser unit to ensure proper airflow. Additionally, check for any visible damage or obstructions and have them addressed by a technician.

1.8 Too Low Supply Voltage

Inadequate voltage supply can cause your AC to function inefficiently, leading to poor cooling performance.

Solution: Have an electrician check the voltage supply to your AC unit. If it's too low, they can recommend appropriate solutions to stabilize the voltage.

1.9 Too High Outdoor Unit Temperature

Excessive heat around the outdoor unit can impede its ability to dissipate heat effectively.

Solution: Provide shade or better ventilation to the outdoor unit if it's exposed to direct sunlight or high temperatures.

Figure 5: Outdoor units of air conditioner.

1.10 Refrigerant Leak/Insufficient Refrigerant

Refrigerant is the lifeblood of your AC system. A leak or insufficient refrigerant can hinder the cooling process.

Solution: Contact a professional HVAC technician to detect and repair any refrigerant leaks. They will also recharge the system with the appropriate amount of refrigerant.

1.11 Faulty Compressor

The compressor is the heart of your AC system. It's responsible for pressurizing the refrigerant and ensuring efficient heat exchange. If the compressor is not functioning correctly, your AC may not cool despite the fan working.

Solution: Replacing a faulty compressor is a complex and expensive repair. It's best to consult a qualified technician who can diagnose the issue accurately and recommend the necessary action.

1.12 Too Old Air Conditioner

Over time, the efficiency of an air conditioner naturally decreases, and older units may struggle to cool effectively.

Solution: If your AC unit is very old and continually underperforms, it might be time to consider replacing it with a newer, more energy-efficient model.

Figure 6: An old air conditioner.

2. What to Do If Your Split Air Conditioner Not Cooling But the Fan Is Running

If you've identified the issue causing your split air conditioner to not cool while the fan is running, you can attempt to resolve it using the solutions provided above. However, if the problem persists or if you're unsure about the cause, it's essential to seek professional help. HVAC technicians are trained to diagnose and repair complex issues with air conditioning systems.

Additionally, regular maintenance is key to preventing such problems. Schedule annual maintenance checks for your split AC to ensure it operates at peak efficiency. This includes cleaning coils, checking refrigerant levels, and verifying the overall health of the system.

In conclusion, when your split AC is not cooling your space as it should, it can be due to various factors, ranging from simple issues like dirty filters to more complex problems like refrigerant leaks or a malfunctioning compressor. By understanding these potential causes and following the recommended solutions, you can maintain a comfortable indoor environment and ensure your split AC operates efficiently for years to come. Remember, when in doubt, consult a professional HVAC technician to diagnose and address the issue effectively.