Few things are more frustrating than an AC not cooling house—especially during Houston’s hot and humid summers. You might hear the system running, feel air blowing from the vents, but the temperature in your home just won’t drop.
Many homeowners call us with the same complaint: “My AC is not cooling but it’s running—what’s wrong?” At AC Repair Houston Pros, we know how stressful it is when your home AC is not blowing cool air.
In this guide, we’ll explore the most common reasons your AC runs but not cooling, troubleshooting tips you can try, and when to call for professional AC repair Houston services.
1. Thermostat Issues
Sometimes the problem isn’t the system—it’s the thermostat. If the thermostat is set to cool but AC not turning on, or if the fan is set to “On” instead of “Auto,” the blower may push warm air through the vents without activating the cooling cycle.
✅ Fix:
- Ensure the thermostat is set to “Cool” and fan to “Auto.”
- Replace batteries if needed.
- If you’re asking, “Why is my AC not cooling even though the thermostat looks fine?”—it may be time for a thermostat upgrade.
2. Dirty or Clogged Air Filters
If my AC is not cooling properly, one of the first things we check is the air filter. A clogged filter restricts airflow, causing your AC to run but not cool the house efficiently.
✅ Fix: Replace filters every 1–3 months. Regular AC maintenance Houston keeps airflow steady and prevents breakdowns.
3. Refrigerant Leaks
Refrigerant is the lifeblood of your AC. If there’s a leak, your system may hum along, but AC does not cool as expected.
✅ Fix: Refrigerant leaks require professional repair. If your AC running but not cooling is due to low refrigerant, call AC Repair Houston Pros for fast service.
4. Frozen or Dirty Evaporator Coils
If your home AC not blowing cool air, frozen coils could be to blame. This happens when airflow is restricted or refrigerant levels are off.
✅ Fix:
- Turn off the system and let the coils thaw.
- Replace dirty filters.
- Schedule routine coil cleaning with our HVAC maintenance plans.
5. Blocked or Leaky Ductwork
Your system may be cooling the air, but leaks in your ducts can prevent it from reaching your rooms—leaving you wondering, “Why is my AC not cooling my house?”
✅ Fix: Get ducts inspected for leaks, blockages, or damage. Search air duct repair near me or contact us for duct sealing and repair.
6. Outdoor Unit Problems
If your AC is running but not cooling, check the outdoor condenser. If it’s blocked with debris, overheating, or malfunctioning, your AC does not cool even though it’s on.
✅ Fix: Keep the unit clear of plants, dirt, and debris. Call for professional condenser cleaning if airflow remains restricted.
7. Electrical Failures
Faulty wiring, tripped breakers, or bad capacitors may cause your AC runs but not cooling situation. The fan may blow, but cooling cycles won’t start.
✅ Fix: If you smell burning or breakers keep tripping, shut off the system and call for emergency HVAC service Houston.
8. Aging or Undersized AC Unit
Sometimes the issue is system size or age. An undersized system may leave you saying, “My AC is not cooling my house enough,” while an old, worn-out unit simply can’t keep up with Houston’s heat.
✅ Fix: We offer commercial and residential HVAC services to size, repair, or replace your system for maximum comfort.
✅ Preventing AC Not Cooling Problems
The best way to avoid asking “Why is my AC not cooling?” every summer is prevention:
- Replace filters on time.
- Schedule bi-annual AC maintenance Houston.
- Keep outdoor units clear.
- Inspect ducts for leaks.
- Enroll in HVAC maintenance plans with lifetime warranty options.
✅ FAQs: AC Not Cooling but Running
1. Why is my AC running but not cooling my house?
Possible causes include dirty filters, thermostat issues, refrigerant leaks, or duct problems.
2. What should I check if my AC does not cool?
Check the thermostat, air filter, coils, and ducts before calling a pro.
3. Why is my AC not cooling upstairs?
Often caused by duct design issues, poor insulation, or insufficient system capacity.
4. Can I fix an AC that runs but doesn’t cool myself?
You can try thermostat resets and filter changes. For refrigerant, electrical, or duct issues, call AC Repair Houston Pros.
5. Do you provide 24/7 AC repair in Houston?
Yes! We offer 24 hour AC repair Houston services for HVAC emergencies.
