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Split / Packaged Air Conditioning
Low Cooling Performance Troubleshooting
Diagnose a cooling system that runs but does not meet expected performance — from airflow basics through refrigerant checks.
Safety Notice
Disconnect power before opening panels. Refrigerant work requires EPA 608 certification. Moving fan blades, live electrical, and hot surfaces are present during operation. Wear appropriate PPE.
Step 1
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Confirm the cooling complaint
Verify the customer complaint: system runs but space is warm or not reaching setpoint. Confirm thermostat is set to COOL, fan set to AUTO, and setpoint is below current room temperature. Allow the system at least 10–15 minutes of run time before diagnosing.
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