AC Running But Not Cooling? 7 Causes for San Angelo Homeowners
Your AC is running — you can hear the compressor and feel air from the vents — but your San Angelo home isn’t cooling down. This is one of the most frustrating HVAC problems, especially when outside temperatures hit 100°F. Here are the 7 most common causes.
1. Low or Leaked Refrigerant
Refrigerant is what actually removes heat from your home’s air. If refrigerant leaks out, your system can run all day without cooling effectively. Signs: AC runs constantly, warm air from vents, ice forming on the indoor unit. Solution: A licensed technician must diagnose the leak, repair it, and recharge the refrigerant. Simply adding refrigerant without fixing the leak is a temporary band-aid.
2. Dirty Condenser Coils
Your outdoor unit’s condenser coils release heat. When they’re coated with dirt and debris — common in San Angelo’s dusty environment — heat can’t escape efficiently. Solution: Annual coil cleaning during your spring tune-up prevents this.
3. Clogged Air Filter
A severely clogged air filter restricts airflow to the point where the evaporator coil can’t absorb heat effectively. In San Angelo, filters clog faster than in most areas. Solution: Replace your air filter every 60–90 days, or monthly during peak summer.
4. Failed Capacitor
The capacitor starts the compressor and fan motors. A failed capacitor means one or both motors can’t start properly, reducing cooling capacity dramatically. Signs: clicking sounds when starting, system struggles to start, warm air. Solution: Capacitor replacement is one of the most common and affordable AC repairs — usually $150–$250 including labor.
5. Refrigerant Overcharge
Adding too much refrigerant is as problematic as too little. An overcharged system operates at higher-than-normal pressures, reduces efficiency, and can damage the compressor. Solution: Have a licensed technician measure and correct refrigerant charge.
6. Duct Leaks
Leaking ducts in attic or wall spaces allow cooled air to escape before reaching your living areas. A home with significant duct leakage can lose 20–30% of cooled air. Solution: Professional duct testing and sealing. In San Angelo’s hot attics, duct leaks are both common and costly.
7. Undersized System or Wrong Thermostat Settings
An AC unit that was never the right size for your home will always struggle in San Angelo’s heat. Similarly, a thermostat in direct sunlight or near heat sources will constantly read high and over-run the system. Solution: We can assess whether your system is properly sized and thermostat placement is correct.
Frequently Asked Questions
Q: How much does it cost to fix an AC that runs but does not cool?
A: It depends on the cause. Refrigerant recharge is $150–$400. Capacitor replacement is $150–$250. Coil cleaning is $100–$250. We diagnose the exact cause before quoting repairs.
Q: Can a clogged filter really stop cooling?
A: Yes. A severely clogged air filter reduces airflow enough that the evaporator coil can freeze, actually stopping cooling. San Angelo’s dusty environment means filters need replacement every 60–90 days.
Q: Should I turn my AC off if it is not cooling?
A: If you notice ice on the indoor unit or refrigerant lines, turn the system to ‘fan only’ mode to thaw the ice before calling for service. For other issues, you can leave the system running but call for service promptly.
Most AC-not-cooling problems have straightforward solutions when diagnosed correctly. Early detection and repair always costs less than waiting until the system fails completely. Call San Angelo HVAC Services at (877) 651-9143 for same-day AC repair in San Angelo.