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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

asked 2019-06-19 07:45:52 -0500

Prasanth M gravatar image

updated 2019-07-14 12:39:38 -0500

I used variable volume fan for single zone and the coefficients are C1=0.040759893999999998, c2=0.08804497, c3=-0.072926119999999997, c4=0.94373982300000003, c5=0, the fan pressure was 995 Pa and the flow rate was autosized.

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answered 2019-06-19 11:18:40 -0500

Simply changing the fan does not necessarily mean the air flow rate will change. VAV is typically used with VAV terminal boxes. Were you using VAV terminals with the constant volume fan? What type of HVAC system?

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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.

Prasanth M gravatar image Prasanth M  ( 2019-06-19 23:01:25 -0500 )edit

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

Prasanth M gravatar image Prasanth M  ( 2019-06-20 03:57:00 -0500 )edit

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Asked: 2019-06-19 07:45:52 -0500

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Last updated: Dec 19 '20