Display shows H1 and the interior temperature is much warmer than the set point.

Safety: This is typically an alarm, not an electrical fault, but always unplug the unit before removing panels.

Steps to clear H1:

• Check door seal: Ensure the door is fully closing and the gasket is not warped, torn, or obstructed by shelves or bottles.
• Allow cool-down time: If you recently loaded many warm bottles, allow 12–24 hours for the temperature to stabilize. The H1 alarm may clear automatically once the interior cools.
• Verify cooling operation: Listen for the compressor and fans running. If they are silent for long periods while the interior is warm, there may be a cooling system issue.
• Inspect condenser and ventilation: Clean the condenser coils and ensure proper airflow around the unit. Overheating can reduce cooling capacity.
• Check temperature sensor: If the interior feels cool but the display shows a high temperature, test the cabinet NTC sensor as described for E1 and replace if out of range.
• Reset alarm: Many Arctic King models allow you to silence the alarm by pressing and holding the alarm or power button. This does not fix the cause; ensure cooling is restored.

Call a technician: If the compressor runs continuously but the temperature does not drop, the sealed system may be undercharged or restricted and requires professional service.