Display shows Hi and the unit cannot be set to a higher temperature, or the interior is much warmer than the display suggests.

Safety first: No high-voltage work is needed for basic checks. Unplug the unit if removing panels.

Steps to address Hi:

• 1. Confirm actual temperature: Place a thermometer inside. If the interior is indeed warm, treat this as a cooling performance issue (see related no-cool entries).
• 2. Check door and seal: Ensure the door closes fully and the gasket makes uniform contact. Look for gaps, tears, or warped areas.
• 3. Inspect ventilation: Verify that the cooler has proper clearance and is not installed in a very hot environment.
• 4. Reset alarm: Many STAIGIS models allow clearing the Hi alarm by pressing and holding the power or alarm button for several seconds after the temperature returns to normal.
• 5. Test sensor if reading is inaccurate: If the display shows Hi but the interior is cool, test the cabinet NTC sensor and replace if out of range.

When to call a technician: If Hi persists with correct sensor readings, the main control board may be defective.