Tennessee summers are no joke. When the heat and humidity hit Middle Tennessee, your air conditioner is not just a comfort feature, it is a necessity. So when your AC is running but your home still feels warm, sticky, and uncomfortable, frustration sets in fast.
Many homeowners in Murfreesboro deal with this exact problem every summer. The air conditioner is on, the thermostat is set low, but the house refuses to cool down. You may notice weak airflow, warm air blowing from the vents, or certain rooms that never reach the temperature you want. In a humid climate like ours, even small AC problems can feel overwhelming.
The good news is that not every cooling issue means a major repair. In many cases, there are simple things you can check and fix yourself before calling a professional. Below are the seven most common reasons an AC is not cooling and what you can do before scheduling service.
1. Dirty Air Filter
A dirty air filter is the most common reason an AC is not cooling properly. When the filter becomes clogged with dust, dirt, and pollen, airflow is restricted. Without proper airflow, your system cannot cool your home effectively.
Restricted airflow also forces your AC to work harder, which increases energy bills and can cause long-term damage. In some cases, it can even lead to frozen coils.
To check your air filter, remove it and hold it up to a light. If you cannot clearly see light through it, the filter needs to be replaced.
Replace your air filter every one to three months. Homes with pets, allergies, or high dust levels may need more frequent changes.
Common signs of a dirty filter include weak airflow, ice forming on the unit, and higher utility bills. In Murfreesboro, heavy pollen seasons mean filters clog faster, so regular replacement is especially important.
2. Thermostat Issues
Sometimes the issue is not your air conditioner at all, but the thermostat controlling it. Incorrect settings or minor malfunctions can prevent your AC from cooling properly.
Check that the thermostat is set to cool and not heat. Replace the batteries if they are weak or dead. Make sure the temperature is set lower than the current room temperature.
Thermostat placement also matters. If it is located near windows, lamps, or appliances that generate heat, it may read the room temperature incorrectly.
If your thermostat is inaccurate or unresponsive, recalibration or replacement may be needed to restore proper cooling.
3. Refrigerant Leak
Refrigerant is what allows your air conditioner to remove heat from your home. If your system has a refrigerant leak, it will struggle to cool effectively.
Common signs include warm air coming from vents, ice buildup on the indoor unit, hissing or bubbling noises, and long run times with little cooling.
Refrigerant leaks are serious. They can be harmful to the environment and unsafe if not handled correctly. Because refrigerant is regulated, repairs must be performed by an EPA-certified technician.
This is not a DIY repair. If you suspect a refrigerant issue, professional service is required.
4. Frozen Evaporator Coil
A frozen evaporator coil can completely stop your AC from cooling. This is often caused by restricted airflow or low refrigerant levels.
Signs include ice on copper refrigerant lines, water pooling around the indoor unit, and little to no air coming from vents.
Turn off your air conditioner and allow it to thaw completely. This can take up to 24 hours. After thawing, replace the air filter and make sure all vents are open and unobstructed.
Regular filter changes and maintenance help prevent frozen coils from happening again.
5. Dirty Condenser Coils
The condenser coil is located in the outdoor unit and releases heat from your home. When it becomes covered in dirt, grass, or debris, heat cannot escape properly.
This trapped heat prevents your AC from cooling efficiently and can cause overheating.
Turn off power to the unit and gently hose down the coils. Remove leaves and debris from around the unit. Do not use high pressure, as it can damage the coils.
Annual professional maintenance is recommended for deeper cleaning and peak performance.
6. Faulty Compressor
The compressor is the heart of your air conditioning system. It circulates refrigerant to remove heat from your home.
Signs of compressor problems include loud noises, warm air from vents, frequent breaker trips, and an AC that runs but does not cool.
Compressor repairs are complex and expensive. This is not a homeowner repair.
Depending on the age of your system, replacing the unit may be more cost-effective than repairing the compressor. A professional evaluation is needed.
7. Ductwork Leaks
Leaky ductwork can prevent cool air from reaching your living spaces, even if the AC system itself is working.
Cool air may escape into attics or crawlspaces before it ever reaches your rooms.
Signs of duct leaks include uneven temperatures, high energy bills, and excessive dust.
You can inspect accessible ducts for visible gaps or disconnections, but many leaks are hidden and require professional testing and sealing.
When to Call Airstream Services
Some AC problems should always be handled by a professional. Call for service if you notice electrical issues, refrigerant problems, compressor failure, water leaks, or ice buildup that keeps returning.
Routine maintenance also helps prevent breakdowns and costly repairs. Professional inspections catch small issues early. Emergency service is available 24/7 for urgent cooling problems.
Frequently Asked Questions
Q: How long should it take for an AC to cool a house?
A: A properly working system should lower the temperature by about one degree every 15 to 30 minutes. If it takes longer, there may be a problem.
Q:Why is my AC running but not cooling at night?
A: This can indicate a refrigerant leak, airflow issue, or compressor problem. A professional diagnosis is recommended.
Q:Can I run my AC if it is not cooling properly?
A: No. Running the system without proper cooling can damage the compressor. Turn it off and call a technician.
Q: How often should I service my AC in Murfreesboro?
A: Twice per year. Schedule service in the spring for cooling season and in the fall for heating season.
Q: What temperature should I set my AC to during a Tennessee summer?
A: A setting between 72°F and 76°F offers a good balance of comfort and efficiency.
Need AC Repair in Murfreesboro?
Do not let a broken AC ruin your Murfreesboro summer. If these quick fixes do not solve your cooling problem, Airstream Services is here to help. Our EPA-certified technicians serve Murfreesboro, Smyrna, Franklin, and surrounding Middle Tennessee areas with fast, reliable, same-day service. Call 615-216-5979 or schedule online today to restore comfort to your home.
