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shorowit
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Apr 24, 2026
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| elsif water_heating_system.hpwh_voltage == HPXML::HPWHVoltage120Dedicated | ||
| cop = 3.6 | ||
| else # 120V shared | ||
| cop = 4.2 |
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Need to replace with equations based on UEF. @jmaguire1
| # https://neea.org/img/documents/hpwh-lab-report_ao-smith_hptu_12-09-2015.pdf. | ||
| # More recent products do not show much change to UA values, see 2021 report: | ||
| # https://neea.org/img/documents/Laboratory-Assessment-of-Rheem-Generation-5-Series-HPWH.pdf. | ||
| # FIXME: Is this close enough to the right value for 120V, or do we need new UA values? |
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| cap_coeff = [0.563, 0.0437, 0.000039, 0.0055, -0.000148, -0.000145] | ||
| cop_coeff = [1.1332, 0.063, -0.0000979, -0.00972, -0.0000214, -0.000686] | ||
| elsif water_heating_system.hpwh_voltage == HPXML::HPWHVoltage120Dedicated | ||
| cap_coeff = [0.636, 0.0227, 0.000406, -0.000437, 0.0, 0.0] | ||
| cop_coeff = [1.1798, 0.030, 0.0002063, -0.01935, 0.0001341, -0.000303] | ||
| else # 120V shared | ||
| cap_coeff = [0.813, 0.0160, 0.000537, 0.002032, -0.000086, -0.000069] | ||
| cop_coeff = [1.0132, 0.044, 0.0000117, -0.01113, 0.0000369, -0.000498] |
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Need to double-check that I implemented this correctly. Was seeing an E+ warning about COP curve not 1 at nominal conditions.
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@jmaguire1 I'm pretty sure I implemented the curves correctly. See 120V dedicated here and 120V shared here. Both give E+ warnings that the curves evaluate to ~0.8 at rated conditions.
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| # FIXME: Use HPXML HasMixingValve and MixingValueSetpoint elements? | ||
| # FIXME: Should this be min(125.0, t_set)? |
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- Assuming mixing valve if 120V HPWH (@jmaguire1 will double check).
- Default mixing valve setpoint at min(125.0, t_set).
- MixingValueSetpoint must be < WHsetpoint and >= 105F
- Warning that target temp > hot water temp is okay to ignore.
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Pull Request Description
Closes #1427.
Re-implements #1534 off the master branch. Uses the HPXML
HPWHVoltage/HasMixingValue/MixingValveSetpointelements (added here).Example docs for HPWH:
Checklist
Not all may apply:
EPvalidator.sch) has been updatedopenstudio tasks.rb update_hpxmls)HPXMLtoOpenStudio/tests/test*.rband/orworkflow/tests/test*.rb)openstudio tasks.rb update_measureshas been run