What this usually means
Start by confirming that the thermostat is set to COOL and below the indoor temperature. Check the filter and make sure supply and return vents are open.
If the indoor blower runs but the outdoor unit does not, or if both run without cooling, the system needs diagnosis rather than a guessed part replacement.
What you can safely check
- Thermostat mode and setpoint
- Filter condition
- Open supply and return vents
- Whether indoor and outdoor equipment are operating
When to call a professional
Request service when basic settings and airflow checks do not restore cooling, or immediately for ice, burning odors, severe noise or repeated breaker trips.
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