calculation of free air area on a ventilation grill
Posted: Tue Jun 26, 2007 7:21 pm
I have been told/ordered to increase the ventilation area to the housing of our gas central heating boiler room. I presently have two grills of 8000mm squared - that is 80 sq cm. I am required to fit a grill 141 sq cm at the top of the access door to the boiler room and a grill 282 sq cm at the bottom of the door. What sizes of grill will provide the above free area?