F4 code, burner lights then shuts off within a few seconds

Safety first: Turn gas OFF and disconnect power. Allow the burner to cool.

• Clean flame sensor: Remove and gently clean the Giant flame sensor rod with fine abrasive pad to remove oxidation.
• Check ground connections: Ensure the burner assembly and control board ground wires are securely fastened to clean metal surfaces.
• Inspect burner: Clean burner ports and ensure proper alignment. A distorted flame may not fully engulf the sensor.
• Verify gas supply: If other gas appliances are affected, contact your gas supplier. Low pressure can cause weak flame.
• Replace sensor or control: If F4 persists after cleaning and verifying grounds, replace the flame sensor. If still unresolved, the Giant control board may require replacement.