Whirlpool portable or split-type air conditioner shows E4 and may stop cooling or enter protection mode.
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: Turn the unit off and unplug it. Do not attempt to open the sealed refrigeration system yourself.
Steps to address E4:
- Check airflow: Remove and clean the air filter with mild soap and water. Let it dry completely before reinstalling. Ensure supply and return grilles are not blocked by curtains, furniture, or covers.
- Inspect evaporator coil: Remove the front cover and visually inspect the indoor coil. If it is iced over, leave the unit unplugged with the cover off until all ice melts. Do not chip ice with tools.
- Inspect condenser coil: For window and portable units, check the outdoor coil for dirt, lint, or debris. Clean gently with a soft brush or vacuum. Ensure the rear of the unit has at least the clearance recommended in the manual.
- Room conditions: Extremely low room temperature can cause icing. Ensure the room is above the minimum operating temperature specified by Whirlpool.
- Reset: After cleaning and thawing, plug the unit back in and run in FAN mode for 15–20 minutes, then switch to COOL and monitor for E4.
If E4 returns frequently: The unit may have a low refrigerant charge, a failing compressor, or a defective temperature/defrost sensor. These require specialized tools and EPA-certified service. Contact a qualified Whirlpool service technician.