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Split / Packaged Air Conditioning
No Cooling — System Not Running
Diagnose a cooling system that is not starting, not energizing, or where the outdoor unit is completely off.
Safety Notice
Live voltage (240V+) is present at the outdoor disconnect and inside equipment panels. Capacitors store lethal charge even after power is removed — discharge before handling. Keep hands clear of fan blades. This workflow is intended for trained HVAC service technicians only.
Step 1
info
Confirm the complaint
Verify the customer complaint: system is not cooling and appears to not be running at all. Confirm the thermostat is set to COOL, fan set to AUTO, and the setpoint is below current room temperature.
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