I have received this question generated by the LEED v4 Minimum Energy Performance calculator stating "The fan demand (as reported in the Performance Outputs tab) for the baseline and/or proposed exceeds the fan power as reported in the Air-Side HVAC tab (total system fan power) by more than 5%. Ensure that the values reflected in the Air-Side HVAC sheet are accurate and appropriately reflect the modeled fans."
I added the baseline fan demand in the Air-Side HVAC tab based on the values generated from eQuest reflected from what I was required to do according to Appendix G for System 3 and System 9. I added the proposed fan demand in the same tab based on the Mechanical Schedule of the recent project drawings. In eQuest, I made sure the fan power for each unit in the proposed was modeled with the same values taken from the Mechanical Schedule. By that logic, the fan power that eQuest generated for the baseline and proposed models would match the fan demand noted in the Air-Side HVAC tab. After running simulations for both models and adding them to the Performance Outputs tab, the total ventilation fan power for both models exceeded the fan demand for both baseline and proposed in the Air-Side HVAC tab. How can that be? I made sure the fan power for each individual system was identical in the Air-Side HVAC tab and eQuest for both the baseline and proposed models. Even the ventilation operation schedules for both models are identical.
