Outdoor unit or system displays F3; heating or cooling performance is unstable
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: Turn off power before opening the outdoor unit service panel.
Steps to check:
- 1. Locate T4 sensor: On the outdoor unit, the T4 sensor is usually attached near the air intake grille or on the refrigerant piping, exposed to outdoor air.
- 2. Inspect sensor and mount: Ensure the sensor is intact and securely fixed in its bracket or clip. Reattach if loose.
- 3. Check wiring and connector: Follow the sensor wires to the outdoor PCB. Confirm the connector is firmly seated and wires are not cut or pinched.
- 4. Replace sensor if needed: If the sensor is physically damaged or F3 persists, replace it with a compatible Midea outdoor ambient sensor.
When to call a technician: If replacing the sensor does not clear F3, the outdoor PCB may have a defective sensor input and should be diagnosed by a technician.
Repair Difficulty
Required Part
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