Dehumidifier displays E3 and will not dehumidify properly.

Safety: Unplug the dehumidifier before inspection.

Steps:

• Clean the air path: Remove and wash the air filter with mild soap and water. Let it dry completely. Vacuum the intake grille to remove dust that can affect humidity readings.
• Locate the humidity sensor: Typically mounted near the air intake or behind the front grille on Frigidaire units. It may be a small plastic module with vent holes and two or more wires.
• Inspect sensor: Check for dust buildup, corrosion, or physical damage. Gently clean the sensor housing with a dry brush or compressed air; do not wet the sensor.
• Check wiring: Follow the sensor harness to the control board. Ensure the connector is fully seated and wires are not pinched or broken.
• Test operation: Reassemble, plug in, and set the humidity to a low value (e.g., 35%). If E3 reappears, the humidity sensor is likely defective.
• Replace sensor: Order a Frigidaire-compatible humidity sensor for your exact model and replace it, matching wire colors and connector orientation.
• Control board: If replacing the sensor does not clear E3, the main control board may not be processing the sensor signal correctly and may require replacement by a technician.