Question-and-Answer Resource for the Building Energy Modeling Community
 | 1 | initial version |
you'll need to request a performance curve from the manufacturer, and then make a curve in eQUEST.
I don't think you need to worry about the condenser being separate as the heat rejection won't change substantially. Perhaps adding pump power as a process cooling load, and as a metered electric load would be the best way to approximate this. Maybe create an 8760 pump power schedule based on the hourly cooling load from the model.
You can create a water side economizer as a separate chiller on the same chilled water loop, and have a dry cooler selected as your cooling tower option in the condenser loop. Set the condenser pump power to zero.
| | 2 | No.2 Revision |
you'll need to request a performance curve from the manufacturer, and then make a curve in eQUEST. It takes 33 selections to make the necessary curves for an air cooled plant so give your rep a heads up on that.
I don't think you need to worry about the condenser being separate as the heat rejection won't change substantially. Perhaps adding pump power as a process cooling load, and as a metered electric load would be the best way to approximate this. Maybe create an 8760 pump power schedule based on the hourly cooling load from the model.
You can create a water side economizer as a separate chiller on the same chilled water loop, and have a dry cooler selected as your cooling tower option in the condenser loop. Set the condenser pump power to zero.
To elaborate on this you'll need the following components in the chiller plant. Best to build it in the following order too:
CHW loop Condenser water loop CHW pump Condenser water pump Air cooled chiller Water side economizer chiller component heat exchanger as attachment to dry cooler heat exchanger pump as attachment to dry cooler Dry cooler Equipment controller Load managment
Then you'll want to create hourly reports for the pertinent chiller plant values to ensure that it's operating correctly.
Please reply to this post your experience here as this is not very straightforward, and 90.1-2010 is requiring more water side economizing. A reliable method of creating these plants should be recorded.
Good luck
