Gree F3

What does Gree F3 mean?

F3 means the outdoor ambient temperature sensor is open- or short-circuited. In cool, fan or dry mode the indoor fan keeps running while the compressor and outdoor fan stop; in heat all loads stop. The unit displays F3.

Symptoms

• Display shows F3
• In cool/fan/dry the indoor fan runs but compressor and outdoor fan stop; in heat all loads stop
• Unit refuses to cool or heat
• Code appears at power-up or soon after running

Common causes

• Outdoor ambient temperature sensor not connected well
• Temperature sensor damaged
• Connection wire short-circuited or broken
• Main board fault (outdoor unit)

Diagnostic steps

1. 01

   Check the connection terminal

   Verify the terminal between the outdoor ambient sensor and the control board is not loose or poorly connected, and reseat the sensor.

2. 02

   Inspect for shorts

   Check for a short circuit from tripped-over parts on the board and straighten them.

3. 03

   Measure resistance

   Test the sensor against the manual's resistance table; if out of range, replace it with the same model.

4. 04

   Replace the board

   If the sensor and wiring are good, replace the outdoor controller board with one of the same model.

When to call a professional

The outdoor sensor sits in the outdoor unit's control box, which carries line voltage and live components. Verifying it against the resistance table and replacing the outdoor main board are technician-level tasks. If F3 persists after a quick connector check, have a licensed HVAC pro complete the diagnosis safely.