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Chiller cooling capacity sizing

I am sizing a chiller for a project. I did the model using openstudio. I ran the simulation and check the openstudio report in the Plan loops details section. The auto sized chiller cooling capacity is 1,561 Tons which is too high for the building.

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I plotted the chiller evaporator cooling rate for the cooling design day and the maximum value is 1,700 kW (485 Tons) witch is a lot lower than the 1,561 tons.

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Then I open in E+ the IDF file generated in openstudio. I added the ComponentSizingSummary, HVACSizingSummary, FacilityComponentLoadSummary, CoilSizingDetails and ZoneComponentLoadSummary report in the Output:Table:SummaryReport in E+ (by the way I don’t know how to do it in Openstudio. Any help will be appreciated ) Checking the energy plus reports I found:

The 1,561 (5,489,709.35 W) Tons in the OS report are named as: Initial Design Size Reference Capacity. I don’t understand what the meaning of this value is.

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In the Report: Facility Component Load Summary the grand total is 207,9 kW (59.4 Tons) which is a too low for the total building load.

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Then in the next report: Cooling Peak Conditions the Peak Sensible Load with Sizing Factor is 877869.96 [W] (250 Tons).

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I am not sure which value is the correct one for sizing the chiller and I don’t know why there are too different. Is there any other report that I should have checked?

Any help will be appreciated.

Chiller cooling capacity sizing

I am sizing a chiller for a project. I did the model using openstudio. I ran the simulation and check the openstudio report in the Plan loops details section. The auto sized chiller cooling capacity is 1,561 Tons which is too high for the building.

image description

I plotted the chiller evaporator cooling rate for the cooling design day and the maximum value is 1,700 kW (485 Tons) witch is a lot lower than the 1,561 tons.

image description

Then I open in E+ the IDF file generated in openstudio. I added the ComponentSizingSummary, HVACSizingSummary, FacilityComponentLoadSummary, CoilSizingDetails and ZoneComponentLoadSummary report in the Output:Table:SummaryReport in E+ (by the way I don’t know how to do it in Openstudio. Any help will be appreciated ) Checking the energy plus reports I found:

The 1,561 (5,489,709.35 W) Tons in the OS report are named as: Initial Design Size Reference Capacity. I don’t understand what the meaning of this value is.

image description

In the Report: Facility Component Load Summary the grand total is 207,9 kW (59.4 Tons) which is a too low for the total building load.

image description

Then in the next report: Cooling Peak Conditions the Peak Sensible Load with Sizing Factor is 877869.96 [W] (250 Tons).

image description

I am not sure which value is the correct one for sizing the chiller and I don’t know why there are too different. Is there any other report that I should have checked?

Any help will be appreciated.