Energy Analysis Inputs in Revit - Insight EUI versus EnergyPlus Loads

Revit HVAC Zone Settings for Cooling & Heating set point (see image to right) are exported to the gbXML file and are used by DOE2 to calculate the supply air flow rate required to meet design-day heating and cooling loads for the zone. These settings impact the Insight Energy Cost Ratio and the EUI for Insight.

However, these settings are not exported to Energy Plus when calculating the Insight loads calculations. And, they are ignored by Insight loads calculations. The Energy Plus default values can be found in the Insight Loads Report and are: Cooling Setpoint 75F; and Heating Setpoint 65F.

Additionally...

Below are two exports from within Insight, raw DOE2 and gbXML formats respectively, showing that the values set in Revit are propagated to Insight. In order to set these values in Revit and subsequently have them used in Insight, you must use Spaces (not Rooms) and HVAC Zones as well as select to export Spaces data in the Revit Energy Settings dialog.

It is unfortunate that, when present, the H/C set points and moisture control settings are not used by EnergyPlus loads calc. This is what our engineers expect and do in Trane Trace 600. But, in any case, understanding this is very helpful... thus, the reason for this post.

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