I need help in calculation of duct size
For equal friction method using friction loss of 0.1in/100ft for supply and 0.05/100 ft for return, do we need to calculate friction loss for the actual length of duct after taking in to consideration loss added by fittings. Where do we get information about loss added by fitting. till now I am simply aligning 0.1 in against cfm and finding the duct size in the window disregarding duct length.
Best regards
Hamidpia