Short Answer:
If your AC isn’t cooling, the most common issues are dirty air filters, low refrigerant, thermostat problems, or a failing compressor. But let’s unpack that—because Charleston’s heat is no joke.
Common Reasons Your AC Isn’t Cooling
1. Clogged or Dirty Air Filters
- What happens: Blocked airflow = warm rooms.
- Charleston tip: Pollen and humidity here clog filters fast. Check monthly.
2. Low Refrigerant (a.k.a. Freon)
- What it means: Your AC is low on refrigerant or there’s a leak.
- Symptoms: AC blows warm air, ice on the lines, or hissing sounds.
- Expert note: Refrigerant doesn’t get “used up”—a leak means you need a repair.
3. Thermostat Malfunction
- Simple fix: Replace batteries. Then check settings (yes, it happens!).
- Pro tip: Upgrade to a smart thermostat for Charleston’s erratic weather swings.
4. Electrical Issues or Tripped Breaker
- Quick check: Look at your breaker panel. If your AC circuit is tripped, reset it.
- Warning: If it trips repeatedly, call a licensed HVAC tech.
5. Dirty Condenser Coils
- Outdoor problem: That big unit outside? If it’s clogged with leaves, dirt, or salty air (thanks, coastal Carolina), it can’t release heat.
- Fix: Rinse with a garden hose (gently!).
6. Old or Undersized System
- Charleston homebuyer alert: Many older homes have undersized or aging systems.
- Sign: If your AC is running constantly but never cooling, it may be time to upgrade.
Semantic Clusters: Other Questions People Ask
Why is my AC running but not cooling the house?
Could be low refrigerant, dirty coils, a faulty compressor, or airflow issues. Get a pro to diagnose.
How can I tell if my compressor is bad?
Loud noises, hard starts, or your AC turning on without cooling. This is a job for an HVAC technician.
How often should I service my HVAC in Charleston?
Twice a year. Spring and fall tune-ups help beat the heat—and extend your system’s life.
Case Study: A Real Charleston AC Rescue
Client: West Ashley homeowner Issue: AC blowing warm air, house hitting 85° Diagnosis: Leaking refrigerant line + dirty coils
Fix: Repaired the line, topped off refrigerant, cleaned the unit
Result: House cooled to 72° in under 30 minutes
Local Expertise: Charleston HVAC Real Talk
We’ve repaired thousands of systems across the Lowcountry—from James Island to Mount Pleasant. If your AC’s struggling, don’t wait until it quits.
We know the salt air, the pollen, and the humidity that’s thick as chowder. Our techs are NATE-certified, locally based, and fast.
Next Step: Book Your AC Diagnostic Today
Don’t sweat it—literally. Schedule your Charleston AC repair or tune-up now:
- Call us at (843) 834-0607
- Book online here
About the Author
John Gradick is a certified HVAC technician with 25+ years of experience serving the Charleston area. He’s the lead tech at Passion Heating & Air and lives in Summerville with his wife and two dogs. When he’s not fixing ACs, he’s fishing on the Ashley River.
