The TROX HESCO duct nozzle diffusers are particularly suitable for rooms with a high air change rate. The diffusers are freely suspended from the ceiling. The air is evenly distributed inside the duct, and discharged into the room causing very little turbulence and induction. Air discharge can be horizontal, downward or upward. Room ventilation is best achieved when the temperature of the supply air is lower than that of the room; the supply air temperature is ideally -2 to -6 K lower than the extract air temperature. Duct nozzle diffusers should not be used for heating.