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 Phoenix, AZ: 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 Phoenix, AZ
- Advanced Air Llc · 2410 S Central Ave, Phoenix, AZ · 14802197866
- Southland Industries · 246 E Watkins St, Phoenix, AZ · 4804234444
- Mosaic · 2800 N Central Ave, Phoenix, AZ · +16235128868
- Arizona Heat Pump Council · 2702 N 3rd St, Phoenix, AZ · +16022487767
- Sunrise Mechanical Inc · 125 N 2nd St Ste 110#354, Phoenix, AZ · 6027141009
- Good Guys HVAC · 101 E Jefferson St, Phoenix, AZ · +16027638503
- American Cooling And Heating · 40 N Central Ave Ste 1400, Phoenix, AZ · 6023413112
- Arizona Air Coolers LLC · 111 E Maricopa Fwy, Phoenix, AZ · +16232021395
Get free quotes from Phoenix, AZ 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.