Unit shows E8 and stops; may occur after long continuous operation in a cold room.

Safety: Unplug the unit. Do not attempt to open the sealed refrigerant system yourself.

User‑level checks:

• Room temperature: Ensure the room is within the operating range specified by Mitsubishi Electric (typically above ~10°C). Move the unit to a warmer room and try again.
• Airflow: Clean the air filter and check that intake and exhaust grilles are not blocked. Vacuum dust from the evaporator and condenser surfaces.
• Defrost: If the evaporator is iced over, leave the unit unplugged with covers open for several hours to fully defrost, then restart.

Technician checks:

• Verify evaporator sensor readings vs actual coil temperature.
• Check for signs of refrigerant leak (oil stains on joints, weak cooling).
• Measure system pressures and superheat/subcooling.

Repair: Replace a faulty evaporator temperature sensor or main control PCB if sensor readings are incorrect. If low refrigerant or a leak is confirmed, a certified technician must repair the leak, replace the filter‑drier if fitted, evacuate, and recharge the system.