For FL-140 and FL-706 it’s necessary to check the flow of the air to be filtered comparing it with the one of PK-140- For FL-421 the flow to be sucked is the one of the fan U-421 which is 6.500 Nm3/h (corresponding to approx. at 9.000 m3/h), not 6.500 6500 m3/h as indicated in your drawing- Design temperature ha sto be 140°C, being operating temperature 100° - 110°C. Your drawing indicates a temperature