MSF-24CRN1 Ionizer Release negative ion to eliminate odor, dust, smoke and pollen particles to give fresh and healthy air. Louver Position Memory When you start the unit, the angle of horizontal louver will automatically move to the same position as you set previously. Refrigerant Leakage Detection With this new technology, the indoor unit will alarm when the refrigerant leakage reach to a certain level amount to protect the compressor.