Unit will not run, display shows E1 shortly after power-up

Safety first: Disconnect the air conditioner from mains power before removing any covers. Capacitors on the control board can hold charge; avoid touching bare terminals.

Steps to check and correct:

• Power reset: Unplug the unit for 5–10 minutes, then reconnect. If E1 returns immediately, continue.
• Access the front panel: Remove the front grille and filter to access the indoor sensor harness (usually clipped near the evaporator coil or behind the air intake on Electrolux units).
• Inspect the sensor: Look for a small thermistor (NTC) probe attached to the air intake or coil with two thin wires going to the control board. Check for broken, pinched, or corroded wires and loose connectors. Reseat the connector firmly.
• Test resistance: With power still disconnected, use a multimeter on ohms to measure the sensor. At room temperature (~25°C), most Electrolux NTC sensors read between 5–20 kΩ. If it reads open (OL) or near 0 Ω, the sensor is defective.
• Replace if faulty: If readings are out of spec, replace the indoor ambient NTC sensor with an Electrolux-compatible part. Route the new sensor away from sharp metal and secure it in the original clip.
• Check the PCB: If the sensor tests good but E1 persists, inspect the indoor main PCB for burnt components or corrosion at the sensor input. If damage is visible or other functions are erratic, the board may need replacement.

When to stop: If you are not comfortable testing live circuits or replacing the control board, contact an authorized Electrolux service technician.