I used variable speed fan in my air loop for energy savings but the power consumption was not reduced. How to give correct coefficients for my model? Thanks in advance

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First I thank you for your reply. My HVAC system is a water cooled chilled system for a single floor commercial building with 59 thermal zones. I used FCU in each zone initially with constant volume fan and constant volume terminal box. Then I replaced constant volume fan with variable volume fan and constant volume terminal box for energy savings. The later combination did not work as expected.

Hi Sir, I added VAV terminal box with the VAV fan. Now it works perfectly. Thank you once again for your valuable suggestion.