Why is my AC running but not cooling?
If the indoor blower runs but the air is not cold, the power supply is fine and the fault is on the refrigeration or airflow side: a frozen evaporator coil, a compressor that is not starting, a refrigerant leak, or a condenser coil so packed with debris that it cannot reject heat. Turn the system off before the coil ices further.
Four faults, in the order they turn up here
Blower running, air warm- Frozen evaporator coil. Restricted airflow — a blocked filter, a crushed flex duct, a closed return — or low charge. The blower keeps running and pushes room-temperature air over a block of ice. Switch to fan only and let it thaw before anyone touches it.
- The compressor is not starting. The outdoor fan may still spin. A weak run capacitor stops a compressor exactly like a dead one does, which is why the microfarad reading matters: $150–$400 against $850–$2,400.
- Low refrigerant. Refrigerant is not consumed, so low charge means a leak. On an R-410A system the repair question now carries a parts-availability question with it — the transition.
- The condenser cannot reject heat. The oak canopy over Spring Oaks, Weathersfield and Oakland Estates shades the unit and then packs the coil with leaf litter. A coil that cannot shed heat cannot cool the house, however well the compressor runs.
The one that is not a fault at all
Cold and clammyCold but clammy is not the same complaint as warm air, and it is not a breakdown. At roughly 75% average relative humidity, removing moisture takes run time. A system with too much capacity satisfies the thermostat quickly, shuts off, and never runs long enough to dehumidify. The house reads as damp and the instinct is to turn the thermostat down, which makes it worse.
Small attached units are the most exposed to this, and 61.65% of this city's units are multi-family.
Humidity: NOAA 1991–2020 US Climate Normals, Orlando International Airport (USW00012815). Housing mix: City of Altamonte Springs CITY PLAN 2030, Housing Element DIA, Tables 3.1–3.2.
What the fix is likely to cost
Researched ranges| What is being priced | Researched range | What moves it |
|---|---|---|
| Run capacitor | $150–$400 | Florida market, parts and labour. National average around $250. Quoted metro ranges: Tampa Bay $279–$425, Cape Coral $150–$350, Naples $225–$475, Fort Lauderdale $270–$390. |
| Compressor | $850–$2,400 | What most US homeowners pay, against a national average of about $1,600. Broader industry quotes run $1,200–$3,500 depending on system type, refrigerant and labour complexity. |
| Full changeout, for comparison | $6,500–$11,000 | Full central system replacement quoted for the Altamonte Springs area, varying with home size, efficiency, duct condition and permitting. Labour is commonly 30–50% of the total and runs at the top of that band in older homes. |
Sources: Angi (capacitor), HomeAdvisor and This Old House (compressor), a Central Florida contractor's published Altamonte Springs replacement range and Florida PACE (replacement). Compiled September 2026.