Why is my AC running but not cooling?
An AC that runs without cooling is most often a dirty filter choking airflow, a failed capacitor, or low refrigerant from a leak. The filter you can fix in two minutes; a frozen coil means shut it off and let it thaw before a tech comes, or the real problem can't be diagnosed.
Likely causes
- Clogged filter — Starved airflow freezes the coil and kills cooling — check this first, always.
- Failed capacitor — The outdoor fan or compressor won't start properly; a common, relatively cheap repair.
- Refrigerant leak — Ice on the refrigerant lines plus weak cooling. Refilling without fixing the leak buys weeks, not years.
- Dirty outdoor condenser — Cottonwood, grass, and debris insulate the coil so heat can't escape.
What you can check yourself
- Replace the filter. If the indoor coil is iced, turn the system off (fan on) for 3–4 hours to thaw.
- Clear debris from around the outdoor unit — 2 feet of clearance on all sides.
- Check that the thermostat is on 'cool' and below room temperature (it happens more than anyone admits).
Typical cost
Typical repairs in Houston, TX: capacitor $150–$350; refrigerant leak repair + refill $450–$1,200; fan motor $300–$600.
When to call a pro
Ice keeps returning, the breaker trips, or it blows warm after a filter change and thaw — those need a tech, and running it meanwhile can kill the compressor.
HVAC pros in Houston, TX
- Hot Water & Water Heaters Houston TX · 3711 Travis St, Houston, TX · 2813560071
- Services By Reliant · 910 Louisiana St, Houston, TX · +18554575700
- Air Duct Cleaner Houston · 700 Milam St, Houston, TX · (346) 437-3407
- Top Notch AC Repair Houston · 945 Capitol St, Houston, TX · +13466374055
- Tempertech A/C & Heating Llc · 801 Travis St Suite 2101 #817, Houston, TX · +18329943312
- FreshAir Duct Care · 1000 Main St Ste 1755, Houston, TX · +18328020544
- Aura Service Pro · 1301 Fannin St Ste 2440, Houston, TX · 18328030707
- Hot Water - Heater Group. · 301 Main St, Houston, TX · 3464437661
Get free quotes from Houston, TX pros →
Data by Servik — verified local pros from official license records and public sources. Cost figures are typical ranges, not quotes; a pro's written estimate is the real number.