Philips humidifier or dehumidifier displays HI for humidity or temperature and may not regulate properly.

Safety: No immediate hazard, but unit may not control correctly.

• Check environment: Ensure the appliance is not placed directly next to a heater, radiator, or in direct sunlight.
• Relocate sensor: If the sensor is external or on a cable, ensure it is not in a hot or steamy airflow.
• Clean sensor: Lightly clean the humidity/temperature sensor area with a dry brush to remove dust.

If HI persists in normal conditions, the sensor module may be defective and should be replaced.