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Design Builder ASHP Model - COP Remains Constant

Hello, I am a beginner on Design Builder and modelling an ASHP for my university project and after a bit of help. I have essentially used the DB template for an ASHP but have entered my own COPRFT and CAPRFT performance curves to model the DX coil. For my project I would like to show the variations in the ASHP COP throughout the year, however the COP remains pretty constant all the way though. Based on the performance curves I have entered there should be a clear degradation in COP when the outside temperatures drop in the winter months. Any ideas?

Design Builder ASHP Model - COP Remains Constant

Hello, I am a beginner on Design Builder and modelling an ASHP for my university project and after a bit of help. I have essentially used the DB template for an ASHP but have entered my own COPRFT and CAPRFT performance curves to model the DX coil. For my project I would like to show the variations in the ASHP COP throughout the year, however the COP remains pretty constant all the way though. Based on the performance curves I have entered there should be a clear degradation in COP when the outside temperatures drop in the winter months. Any ideas?

Design Builder ASHP Model - COP Remains Constant

Hello, I am a beginner on Design Builder and modelling an ASHP for my university project and after a bit of help. I have essentially used the DB template for an ASHP but have entered my own COPRFT and CAPRFT performance curves to model the DX coil. For my project I would like to show the variations in the ASHP COP throughout the year, however the COP remains pretty constant all the way though. Based on the performance curves I have entered there should be a clear degradation in COP when the outside temperatures drop in the winter months. Any ideas?

EDIT: See screenshots below (I am unsure how to plot a COP graph with design builder so I divided the coil heating rate by the coil electricity rate), actually the COP varies very slightly by about 0.1 and drops in the Summer.

coefficient 6 coefficient 5 coefficient 4 coefficient 3 coefficient 2 coefficient 1 -0.0004052715 -0.0003111287 0.0384748935 0.0000044789 -0.0102478525 1.0835128015

R=0.988363689

image descriptionimage description image description

Design Builder ASHP Model - COP Remains Constant

Hello, I am a beginner on Design Builder and modelling an ASHP for my university project and after a bit of help. I have essentially used the DB template for an ASHP but have entered my own COPRFT and CAPRFT performance curves to model the DX coil. For my project I would like to show the variations in the ASHP COP throughout the year, however the COP remains pretty constant all the way though. Based on the performance curves I have entered there should be a clear degradation in COP when the outside temperatures drop in the winter months. Any ideas?

EDIT: See screenshots below (I am unsure how to plot a COP graph with design builder so I divided the coil heating rate by the coil electricity rate), actually the COP varies very slightly by about 0.1 and drops in the Summer.

coefficient 6 coefficient 5 coefficient 4 coefficient 3 coefficient 2 coefficient 1 -0.0004052715 -0.0003111287 0.0384748935 0.0000044789 -0.0102478525 1.0835128015Coefficients:

1: 1.0835128015 2: -0.0102478525 3: 0.0000044789 4: 0.0384748935 5: -0.0003111287 6: -0.0004052715

X range: 20 to 45 Y range: -10 to 20

R=0.988363689

image descriptionimage description image description

Design Builder ASHP Model - COP Remains Constant

Hello, I am a beginner on Design Builder and modelling an ASHP for my university project and after a bit of help. I have essentially used the DB template for an ASHP but have entered my own COPRFT and CAPRFT performance curves to model the DX coil. For my project I would like to show the variations in the ASHP COP throughout the year, however the COP remains pretty constant all the way though. Based on the performance curves I have entered there should be a clear degradation in COP when the outside temperatures drop in the winter months. Any ideas?

EDIT: See screenshots below (I am unsure how to plot a COP graph with design builder so I divided the coil heating rate by the coil electricity rate), actually the COP varies very slightly by about 0.1 and drops in the Summer.

Coefficients:

1: 1.0835128015 2: -0.0102478525 3: 0.0000044789 4: 0.0384748935 5: -0.0003111287 6: -0.0004052715

X range: 20 to 45 Y range: -10 to 20

R=0.988363689

image descriptionimage description image descriptionimage description