Display shows H1 or HI; audible alarm sounds and interior temperature is too warm.

Safety: No internal electrical work is required for basic checks, but unplug the unit before removing panels.

Immediate checks:

• Ensure the door is fully closed and the gasket is sealing all around. Look for items blocking the door.
• Confirm that the freezer has not just been loaded with a large quantity of unfrozen food; this can trigger a temporary high-temp alarm.
• Press the alarm reset or mute button (if available) to silence the alarm while troubleshooting.

If temperature remains high:

• Listen for the compressor and fans. If they are not running at all, check that the unit is plugged in and the outlet has power.
• Inspect the condenser coils at the back or underneath. Clean heavy dust buildup with a soft brush and vacuum to improve cooling efficiency.
• Verify that the freezer is not placed in a very hot or unventilated space; ensure several inches of clearance around the cabinet.

Advanced checks:

• If the compressor runs continuously but the freezer does not cool, there may be a sealed system issue (low refrigerant, restriction) that requires a professional technician.
• If the display temperature seems inaccurate, test the cabinet thermistor as described for code E1 and replace if faulty.

Monitor: After corrections, allow 12–24 hours for the freezer to pull down to set temperature. The H1/HI alarm should clear automatically once temperature is within range.