Update HVAC models per RESNET HVAC addendum #1879
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…o resnet_heat_pump
…same resnet updates, remove in.schedules.csv in test_hvac.rb
…-HPXML into resnet_heat_pump
…o resnet_heat_pump
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| if (not heating_system.attached_cooling_system.nil?) && (not heating_system.attached_cooling_system.compressor_type.nil?) | ||
| # Based on RESNET DX Modeling Appendix | ||
| heating_system.fan_model_type = (heating_system.attached_cooling_system.compressor_type == HPXML::HVACCompressorTypeSingleStage) ? HPXML::HVACFanModelTypePSC : HPXML::HVACFanModelTypeBPM |
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For attached heating and cooling systems, grab the cooling compressor type first to default, otherwise follow the previous HEScore assumption (based on efficiency)
| cooling_system.fan_model_type = (cooling_system.compressor_type == HPXML::HVACCompressorTypeSingleStage) ? HPXML::HVACFanModelTypePSC : HPXML::HVACFanModelTypeBPM | ||
| cooling_system.fan_model_type_isdefaulted = true | ||
| elsif [HPXML::HVACTypeMiniSplitAirConditioner].include? cooling_system.cooling_system_type | ||
| cooling_system.fan_model_type = HPXML::HVACFanModelTypeBPM |
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Always assume BPM for minisplit, as they're variable speed systems?
| heat_pump.fan_model_type = (heat_pump.compressor_type == HPXML::HVACCompressorTypeSingleStage) ? HPXML::HVACFanModelTypePSC : HPXML::HVACFanModelTypeBPM | ||
| heat_pump.fan_model_type_isdefaulted = true | ||
| elsif [HPXML::HVACTypeHeatPumpGroundToAir].include? heat_pump.heat_pump_type | ||
| if heat_pump.heating_efficiency_cop > 8.75 / 3.2 # HEScore assumption |
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This is kept the same as previous assumptions, need to discuss when we have two speed/var speed GSHP capabilities. Not sure for that case should it follow the RESNET assumption dependent on speed number or should it be something else (out of RESNET scope).
| fan_power = max_fan_power * (fan_ratio**index) | ||
| else | ||
| # psc fan | ||
| fan_power = max_fan_power * fan_ratio * (0.3 * fan_ratio + 0.7) |
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Different fan power equations
| @@ -4489,21 +4511,19 @@ def self.calc_ceer_from_eer(cooling_system) | |||
| def self.set_fan_power_rated(hvac_system, use_eer_cop) | |||
| hvac_ap = hvac_system.additional_properties | |||
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| # Based on RESNET DX Modeling Appendix | |||
| psc_ducted_watts_per_cfm = 0.414 # W/cfm, PSC fan | |||
| psc_ductless_watts_per_cfm = 0.414 # W/cfm, PSC fan | |||
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So far as I can tell, psc_ductless_watts_per_cfm is not used for any case. Ductless minisplit is always var speed and defaulted to bpm fans. Room AC and PTHPs are outside the scope.
| @@ -5076,7 +5096,7 @@ def self.calculate_heat_pump_defrost_load_power_watts(heat_pump, unit_multiplier | |||
| end | |||
| # cooling capacity and airflow are already with unit multiplier, calculate the capacity w/o multiplier | |||
| nominal_cooling_capacity = heat_pump.cooling_capacity / unit_multiplier | |||
| defrost_power_fraction = (max_heating_airflow / design_airflow)**3 | |||
| defrost_power_fraction = calculate_fan_power_from_curve(1.0, max_heating_airflow / design_airflow, heat_pump) | |||
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This should call the calculate_fan_power_from_curve in the first place, so I captured it here.
…o resnet_heat_pump
…-HPXML into resnet_heat_pump
Pull Request Description
closes #1871
Checklist
Not all may apply:
EPvalidator.xml) has been updatedopenstudio tasks.rb update_hpxmls)HPXMLtoOpenStudio/tests/test*.rband/orworkflow/tests/test*.rb)openstudio tasks.rb update_measureshas been run