Unit displays E4 and compressor does not start or shuts off quickly; may occur during very hot operation.

Safety first: Disconnect power. The outdoor coil and compressor area may be hot; allow components to cool before touching.

Steps to address E4 (high-pressure/overheat):

• Clean the condenser coil: Remove the outer cover to expose the condenser. Use a soft brush or vacuum to remove dirt, lint, and debris from the fins. For heavy buildup, use a coil cleaner approved for aluminum fins, following label directions.
• Check condenser fan operation: Restore power briefly and observe whether the outdoor fan starts and runs at full speed when cooling is called. If the fan does not run or is slow/noisy, disconnect power and test/replace the condenser fan motor and capacitor.
• Verify airflow around unit: Ensure the rear of a window or PTAC unit is not blocked by covers, plants, or walls. Maintain several inches of clearance on all sides.
• Inspect high-pressure switch (if equipped): Some Amana models use a resettable or auto-reset high-pressure switch in series with the compressor. Check wiring and continuity with power off. Replace if open when system is cool and pressures are normal.
• Reset and test: After cleaning and repairs, allow the unit to cool for 20–30 minutes, then restore power and test cooling. If E4 returns quickly, a refrigerant or compressor issue may exist and requires a licensed HVAC technician.

Do not attempt to open the sealed refrigeration system yourself; refrigerant work must be done by certified personnel.