Determine the impellar diameter required based on a new water demand of hot water circulating system. D1=D2 x (F1 divided by F2). D1=New pump diameter. D2=Present pump diameter(9″). F1=new GPM(200). F2=Present GPM(120).

Determine the impellar diameter required based on a new water demand of hot water circulating system. D1=D2 x (F1 divided by F2). D1=New pump diameter. D2=Present pump diameter(9″). F1=new GPM(200). F2=Present GPM(120).