Indoor unit runs but no cooling; air is room temperature and outdoor unit does not start
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Possible Causes
How to Fix / Troubleshooting
Safety first: Only inspect breakers and disconnects you can safely access. Do not remove covers from live electrical panels.
Steps to try:
- Check breakers: Locate the dedicated breaker for the outdoor unit in your main panel. If tripped, reset once. If it trips again, do not continue resetting.
- Inspect outdoor disconnect: Verify the pull-out or switch near the outdoor unit is fully inserted/on.
- Listen for operation: With the indoor unit calling for cooling, listen at the outdoor unit for any hum or click. Total silence suggests no power or a failed PCB.
- Confirm thermostat/remote settings: Ensure the system is in COOL mode with a setpoint at least 3–5°F (2–3°C) below room temperature.
When to call a pro: If power is present but the outdoor unit does not start, a technician must test the PCB, contactor (if used), and compressor.
Repair Difficulty
Required Part
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