If your AC is running but the house won't cool in Austin, the most common causes are a clogged filter, an outdoor coil packed with cedar pollen and dust, a weak capacitor after a string of 100°F days, low refrigerant from a leak, a frozen indoor coil, or hail-damaged condenser fins. Check the filter, breaker, and thermostat first, make sure the outdoor fan spins, and look at the fins. If the outdoor unit runs but the air at the vents is warm, turn the system off and call a licensed tech before a cheap repair becomes a compressor.
The five-minute checks before you call anyone
Thermostat. COOL mode, setpoint below room temperature, fan on AUTO.
Filter and coil. Cedar and oak pollen load filters fast in spring, and the outdoor coil can be matted with it. Replace the filter; with the power off, rinse the coil gently from the inside out.
Breaker, outdoor unit, fins. Reset a tripped breaker once. Confirm the fan spins. If the fins are dented flat from hail, the unit can't reject heat and needs a fin comb or a claim.
Why Central Texas systems stop cooling in summer
Heat. Forty-plus 100°F days in a row is normal now. Capacitors weaken with every hot week, and compressors overheat and trip in the afternoon.
Pollen and hail. Spring pollen clogs coils; spring hail dents them. A unit that cooled fine in April and struggles in June often has both problems.
Refrigerant leaks and frozen coils. Gradually weaker cooling points to a slow leak. Low charge or low airflow freezes the indoor coil, which then blows warm air until it thaws.
When to shut it off and get a tech out today
Turn the system off if the outdoor unit runs but the indoor air is warm, if you see ice on the copper lines, or if it short-cycles. Continuing to run it risks the compressor.
In peak season, Austin contractors triage no-cool calls. Say it's a no-cool and mention any elderly residents, infants, or medical conditions in the home.
LocalFixQuotes is not a contractor. We match Austin homeowners with independent, TDLR-licensed HVAC contractors who diagnose and quote the repair. It's free and there's no obligation to hire.
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