F3
Gree Split AC
Severity: ModerateWhat Does This Error Mean?
F3 means the temperature sensor on the outdoor condenser coil has a fault. This sensor monitors coil temperature to protect the system from overheating. A technician needs to inspect and likely replace the sensor or its wiring.
Affected Models
- Gree FAIRY Series
- Gree LOMO Series
- Gree U-MATCH Series
- Gree PULAR Series
- Gree Inverter Split System
Common Causes
- Sensor wire broken or cut inside the outdoor unit
- Sensor clip dislodged from the condenser coil tube it is meant to monitor
- Weather or UV damage degrading the sensor probe over time
- Connector at the outdoor PCB loose or corroded
- Sensor resistance drifted out of acceptable range due to age
How to Fix It
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Turn the AC off at the circuit breaker and allow the system to rest for 5 minutes.
A power cycle clears temporary sensor reading errors. If F3 was a one-time glitch, it may not return.
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Restart and monitor. If F3 reappears, note whether it shows up immediately or only after the unit runs for a few minutes.
Immediate F3 usually means an open circuit (broken wire). F3 that appears after running may indicate a connector that loosens under vibration.
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Do not attempt to open the outdoor unit — call a qualified technician.
The outdoor unit capacitors can store a lethal charge even after power is removed. Leave all internal inspection to a professional.
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Tell the technician exactly when F3 appears (immediately on startup, or after running) — this helps them diagnose faster.
Immediate errors point to wiring breaks. Intermittent errors point to loose connectors or a sensor that fails when hot.
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Ask the technician to check whether the sensor clip is seated firmly on the coil pipe.
The sensor clip can vibrate loose over time. If reseating it fixes the problem, no parts replacement is needed.
When to Call a Professional
Call a technician to inspect the outdoor unit sensor and wiring. The outdoor unit contains high-voltage components — do not open it yourself. Sensor replacement is typically a low-cost repair when caught early.
Frequently Asked Questions
What does the outdoor coil sensor actually do?
It measures the temperature of the condenser coil during operation. The AC uses this reading to protect the system from overheating in cooling mode and freezing in heating mode. Without it, the unit cannot regulate condenser temperature safely.
Will F3 cause the AC to stop working completely?
Most Gree models shut down or limit operation when a protection sensor fails. This is a safety measure — without coil temperature data, the system cannot prevent overheating. Repair it promptly to restore full cooling or heating.
Is the F3 sensor the same as the F2 sensor?
No — F2 is the outdoor air temperature sensor and F3 is the outdoor coil pipe sensor. They are physically different sensors at different locations on the outdoor unit. Both can fail independently, and each triggers its own fault code.