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Water to Air heatpump curves - cooling mode

asked 2016-04-27 04:53:32 -0500

lutinfr's avatar

updated 2016-05-06 11:06:36 -0500

In energyplus or OpenStudio, when editing Cooling performance curves of Waterto Air heatpump, there are only 5 coefficients for both "Total cooling" and "Cooling Power". Only Sensible Cooling has 6 coefficients. I know that all the curves are Bi-quadratic, then normally they have 6 coefficients. So the question is: How do I treat data when generating my own curve. Generate 6 coefficients then use 5, abandon constant value. Or tell excel to force constant to zero ?

Thank you.

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Please read both the input output reference and then come back if you need something more. See here to see the equation with the the 5 coefficients...

Julien Marrec's avatar Julien Marrec  ( 2016-04-27 05:29:26 -0500 )edit

Also please use existing tags whenever possible.

MatthewSteen's avatar MatthewSteen  ( 2016-04-27 07:41:02 -0500 )edit

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answered 2016-05-03 09:13:29 -0500

updated 2016-05-03 09:18:05 -0500

The curves for Coil:Cooling:WaterToAirHeatPump:EquationFit are not bi-quadratic. See the Engineering Reference, "Unitary Water-To-Air Heat Pump" for the equations.

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There is a spreadsheet tool available to help generate these coefficients for water-to-air and water-to-water heat pumps, both the equation fit and parameter estimation types. See the Extrastab at then scroll down to "Additional Release Components". The link there will take you to the downloads area of the helpdesk, select Release_pieces then HeatPump WatertoWater WatertoAir Spreadsheets and Docs.

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Thank you very much, I was missed understand between E+ and IESVE, they are completely different when modeling Water to Air Heatpump. Problem is now solved.

lutinfr's avatar lutinfr  ( 2016-05-05 21:53:43 -0500 )edit

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Asked: 2016-04-27 04:53:32 -0500

Seen: 722 times

Last updated: May 05 '16