Display shows HI and unit may not cool effectively or may cycle oddly.

Safety: Unplug before accessing internal components.

• Verify environment: Check that the room temperature is not excessively high beyond the unit's design (e.g., in a garage or sunroom over 95–100°F / 35–38°C).
• Relocate heat sources: Ensure the sensor area is not directly exposed to sunlight, lamps, or electronics.
• Check sensor placement: Confirm the ambient sensor is in the return air stream, not tucked behind insulation or near the condenser.
• Replace sensor: If HI appears at normal room temperatures, replace the ambient temperature sensor.