The display shows H1, and the cabinet temperature is higher than the setpoint; an alarm may sound.

Safety: No internal electrical work is required for basic checks, but unplug the unit if you remove panels.

Steps:

• Check door and gasket: Ensure the door is fully closed and the Transtherm gasket is sealing all around. Look for gaps, a torn gasket, or misaligned hinges.
• Allow recovery time: If you recently loaded many warm bottles, allow 12–24 hours for the temperature to stabilize. H1 may clear on its own.
• Verify fan and compressor: Confirm that the compressor and interior fan run when cooling is demanded. If either is not running, investigate the fan motor, start relay, or control board as separate faults.
• Clean condenser: Vacuum dust from the condenser coil to improve cooling efficiency.
• Check ambient conditions: Ensure the cabinet is not installed in a very hot environment beyond its rated ambient temperature.

When to call a technician: If H1 persists despite good airflow, a sealed door, and normal fan/compressor operation, a sealed-system issue (refrigerant leak, restricted capillary, weak compressor) is likely and requires professional service.