ANSI 301-2022: Airflow

Changelog.md

@@ -7,6 +7,7 @@ __New Features__
   - The `ElectricAuxiliaryEnergy` input for boilers is no longer used.
 - **Breaking change**: ERI_Results.csv and ERI_Worksheet.csv combined into a single ERI_Results.csv that better reflects the current ERI calculation components; additional fields (e.g., PEfrac) added and a few renamed/removed.
 - **Breaking change**: Each `VentilationFan` must have one (and only one) `UsedFor...` element set to true.
+- Allows `AverageCeilingHeight` to be optionally provided for infiltration calculations.
 - Ground source heat pump model enhancements.
 - Allows `Roof/RadiantBarrier` to be omitted; defaults to false.
 - Adds more error-checking for inappropriate inputs (e.g., HVAC SHR=0 or clothes washer IMEF=0).

docs/source/workflow_inputs.rst

@@ -135,15 +135,16 @@ HPXML Building Construction
 
 Building construction is entered in ``/HPXML/Building/BuildingDetails/BuildingSummary/BuildingConstruction``.
 
-  =======================================  ========  =========  =================================  ========  ========  =======================================================================
-  Element                                  Type      Units      Constraints                        Required  Default   Notes
-  =======================================  ========  =========  =================================  ========  ========  =======================================================================
-  ``ResidentialFacilityType``              string               See [#]_                           Yes                 Type of dwelling unit
-  ``NumberofConditionedFloors``            double               > 0                                Yes                 Number of conditioned floors (including a basement)
-  ``NumberofConditionedFloorsAboveGrade``  double               > 0, <= NumberofConditionedFloors  Yes                 Number of conditioned floors above grade (including a walkout basement)
-  ``NumberofBedrooms``                     integer              > 0                                Yes                 Number of bedrooms
-  ``ConditionedFloorArea``                 double    ft2        > 0                                Yes                 Floor area within conditioned space boundary
-  =======================================  ========  =========  =================================  ========  ========  =======================================================================
+  =============================================================  ========  =========  =================================  ========  ========  =======================================================================
+  Element                                                        Type      Units      Constraints                        Required  Default   Notes
+  =============================================================  ========  =========  =================================  ========  ========  =======================================================================
+  ``ResidentialFacilityType``                                    string               See [#]_                           Yes                 Type of dwelling unit
+  ``NumberofConditionedFloors``                                  double               > 0                                Yes                 Number of conditioned floors (including a basement)
+  ``NumberofConditionedFloorsAboveGrade``                        double               > 0, <= NumberofConditionedFloors  Yes                 Number of conditioned floors above grade (including a walkout basement)
+  ``AverageCeilingHeight``                                       double    ft         > 0                                No        8.2       Floor to ceiling height within conditioned space
+  ``NumberofBedrooms``                                           integer              > 0                                Yes                 Number of bedrooms
+  ``ConditionedFloorArea``                                       double    ft2        > 0                                Yes                 Floor area within conditioned space boundary
+  =============================================================  ========  =========  =================================  ========  ========  =======================================================================
 
   .. [#] ResidentialFacilityType choices are "single-family detached", "single-family attached", or "apartment unit".
          For ENERGY STAR, "single-family detached" may only be used for SF versions and "apartment unit" may only be used for MF versions; "single-family attached" may be used for all versions.
@@ -302,52 +303,52 @@ Note that ELA is different than Equivalent Leakage Area (EqLA), which involves a
 HPXML Attics
 ************
 
-If the dwelling unit has an unvented attic, whether it is within the infiltration volume is entered in ``/HPXML/Building/BuildingDetails/Enclosure/Attics/Attic[AtticType/Attic[Vented="false"]]``.
+If the dwelling unit has an unvented attic, additional information is entered in ``/HPXML/Building/BuildingDetails/Enclosure/Attics/Attic[AtticType/Attic[Vented="false"]]``.
 
   ============================  =======  =====  ===========  ========  =======  ===============================================
   Element                       Type     Units  Constraints  Required  Default  Notes
   ============================  =======  =====  ===========  ========  =======  ===============================================
-  ``WithinInfiltrationVolume``  boolean                      Yes                In accordance with ANSI/RESNET/ICC Standard 380
+  ``WithinInfiltrationVolume``  boolean                      Yes                Included in the air infiltration measurement?
   ============================  =======  =====  ===========  ========  =======  ===============================================
 
-If the dwelling unit has a vented attic, attic ventilation information can be optionally entered in ``/HPXML/Building/BuildingDetails/Enclosure/Attics/Attic[AtticType/Attic[Vented="true"]]/VentilationRate``.
+If the dwelling unit has a vented attic, additional information is entered in ``/HPXML/Building/BuildingDetails/Enclosure/Attics/Attic[AtticType/Attic[Vented="true"]]``.
 
-  =================  ======  =====  ===========  ========  =======  ==========================
-  Element            Type    Units  Constraints  Required  Default  Notes
-  =================  ======  =====  ===========  ========  =======  ==========================
-  ``UnitofMeasure``  string         See [#]_     No        SLA      Units for ventilation rate
-  ``Value``          double         > 0          No        1/300    Value for ventilation rate
-  =================  ======  =====  ===========  ========  =======  ==========================
+  =================================  ======  =====  ===========  ========  =======  ==========================
+  Element                            Type    Units  Constraints  Required  Default  Notes
+  =================================  ======  =====  ===========  ========  =======  ==========================
+  ``VentilationRate/UnitofMeasure``  string         See [#]_     No        SLA      Units for ventilation rate
+  ``VentilationRate/Value``          double         > 0          No        1/300    Value for ventilation rate
+  =================================  ======  =====  ===========  ========  =======  ==========================
 
   .. [#] UnitofMeasure choices are "SLA" (specific leakage area) or "ACHnatural" (natural air changes per hour).
 
 HPXML Foundations
 *****************
 
-If the dwelling unit has an unconditioned basement, whether it is within the infiltration volume is entered in ``Enclosure/Foundations/Foundation/FoundationType/Basement[Conditioned='false']``.
+If the dwelling unit has an unconditioned basement, additional information is entered in ``/HPXML/Building/BuildingDetails/Enclosure/Foundations/Foundation[FoundationType/Basement[Conditioned='false']]``.
 
   ============================  =======  =====  ===========  ========  =======  ===============================================
   Element                       Type     Units  Constraints  Required  Default  Notes
   ============================  =======  =====  ===========  ========  =======  ===============================================
-  ``WithinInfiltrationVolume``  boolean                      Yes                In accordance with ANSI/RESNET/ICC Standard 380
+  ``WithinInfiltrationVolume``  boolean                      Yes                Included in the air infiltration measurement?
   ============================  =======  =====  ===========  ========  =======  ===============================================
 
-If the dwelling unit has an unvented crawlspace, whether it is within the infiltration volume is entered in ``Enclosure/Foundations/Foundation/FoundationType/Crawlspace[Vented='false']``.
+If the dwelling unit has an unvented crawlspace, additional information is entered in ``/HPXML/Building/BuildingDetails/Enclosure/Foundations/Foundation[FoundationType/Crawlspace[Vented='false']]``.
 
   ============================  =======  =====  ===========  ========  =======  ===============================================
   Element                       Type     Units  Constraints  Required  Default  Notes
   ============================  =======  =====  ===========  ========  =======  ===============================================
-  ``WithinInfiltrationVolume``  boolean                      Yes                In accordance with ANSI/RESNET/ICC Standard 380
+  ``WithinInfiltrationVolume``  boolean                      Yes                Included in the air infiltration measurement?
   ============================  =======  =====  ===========  ========  =======  ===============================================
 
-If the dwelling unit has a vented crawlspace, crawlspace ventilation information can be optionally entered in ``/HPXML/Building/BuildingDetails/Enclosure/Foundations/Foundation[FoundationType/Crawlspace[Vented="true"]]/VentilationRate``.
+If the dwelling unit has a vented crawlspace, additional information is entered in ``/HPXML/Building/BuildingDetails/Enclosure/Foundations/Foundation[FoundationType/Crawlspace[Vented="true"]]``.
 
-  =================  ======  =====  ===========  ========  =======  ==========================
-  Element            Type    Units  Constraints  Required  Default  Notes
-  =================  ======  =====  ===========  ========  =======  ==========================
-  ``UnitofMeasure``  string         See [#]_     No        SLA      Units for ventilation rate
-  ``Value``          double         > 0          No        1/150    Value for ventilation rate
-  =================  ======  =====  ===========  ========  =======  ==========================
+  =================================  ======  =====  ===========  ========  =======  ==========================
+  Element                            Type    Units  Constraints  Required  Default  Notes
+  =================================  ======  =====  ===========  ========  =======  ==========================
+  ``VentilationRate/UnitofMeasure``  string         See [#]_     No        SLA      Units for ventilation rate
+  ``VentilationRate/Value``          double         > 0          No        1/150    Value for ventilation rate
+  =================================  ======  =====  ===========  ========  =======  ==========================
 
   .. [#] UnitofMeasure only choice is "SLA" (specific leakage area).
 

hpxml-measures/Changelog.md

@@ -11,14 +11,17 @@ __New Features__
   - Adds schedule inputs for hot water recirculation pumps and general water use internal gains.
   - Updated water heater installation location defaulting to match ANSI 301-2022
   - Updated calculation of hot water piping length for buildings with both conditioned and unconditioned basements to avoid double counting.
+  - Updates how imbalanced infiltration and mechanical ventilation are combined on an hourly basis.
+  - Small change to default flow rate for imbalanced mechanical ventilation systems.
   - `AverageCeilingHeight` now used in natural ACH/CFM infiltration calculations.
 - **Breaking change**: Replaces `BuildingSummary/Site/extension/GroundConductivity` with `BuildingSummary/Site/Soil/Conductivity`.
 - **Breaking change**: Modeling whole SFA/MF buildings is now specified using a `SoftwareInfo/extension/WholeSFAorMFBuildingSimulation=true` element instead of `building-id=ALL` argument.
 - Allows optional building site inputs (`GeoLocation/Latitude`, `GeoLocation/Longitude`, `Elevation`); useful when located far from, or at a very different elevation than, the EPW weather station.
-- Air source heat pump enhancements:
+- Air source heat pump/air conditioner enhancements:
   - Adds heat pump backup autosizing methodology input (`HeatPumpBackupSizingMethodology`) with choices of "emergency" and "supplemental".
-  - Allows autosizing with detailed performance data inputs for variable-speed systems using `CapacityFractionOfNominal`.
-  - Now defaults to -20F for `CompressorLockoutTemperature` for variable-speed systems.
+  - Allows autosizing with detailed performance data inputs for variable-speed HVAC systems using `CapacityFractionOfNominal`.
+  - Adds maximum power ratio detailed schedule for variable-speed HVAC systems to model shedding controls per [AHRI 1380](https://www.ahrinet.org/search-standards/ahri-1380-i-p-demand-response-through-variable-capacity-hvac-systems-residential-and-small).
+  - Now defaults to -20F for `CompressorLockoutTemperature` for variable-speed heat pump systems.
 - Ground source heat pump enhancements:
   - Allows optional detailed inputs related to geothermal loop (`HVACPlant/GeothermalLoop`).
   - Allows optional ground diffusivity input.

hpxml-measures/HPXMLtoOpenStudio/measure.rb

@@ -448,7 +448,7 @@ def create_unit_model(hpxml, hpxml_bldg, runner, model, epw_path, epw_file, weat
     @hvac_unavailable_periods = Schedule.get_unavailable_periods(runner, SchedulesFile::Columns[:HVAC].name, @hpxml_header.unavailable_periods)
     airloop_map = {} # Map of HPXML System ID -> AirLoopHVAC (or ZoneHVACFourPipeFanCoil)
     add_ideal_system(model, spaces, epw_path)
-    add_cooling_system(model, weather, spaces, airloop_map)
+    add_cooling_system(model, runner, weather, spaces, airloop_map)
     add_heating_system(runner, model, weather, spaces, airloop_map)
     add_heat_pump(runner, model, weather, spaces, airloop_map)
     add_dehumidifiers(runner, model, spaces)
@@ -1570,7 +1570,7 @@ def add_hot_water_and_appliances(runner, model, weather, spaces)
     Waterheater.apply_combi_system_EMS(model, @hpxml_bldg.water_heating_systems, plantloop_map)
   end
 
-  def add_cooling_system(model, weather, spaces, airloop_map)
+  def add_cooling_system(model, runner, weather, spaces, airloop_map)
     conditioned_zone = spaces[HPXML::LocationConditionedSpace].thermalZone.get
 
     HVAC.get_hpxml_hvac_systems(@hpxml_bldg).each do |hvac_system|
@@ -1603,9 +1603,9 @@ def add_cooling_system(model, weather, spaces, airloop_map)
           HPXML::HVACTypeMiniSplitAirConditioner,
           HPXML::HVACTypePTAC].include? cooling_system.cooling_system_type
 
-        airloop_map[sys_id] = HVAC.apply_air_source_hvac_systems(model, cooling_system, heating_system, sequential_cool_load_fracs, sequential_heat_load_fracs,
+        airloop_map[sys_id] = HVAC.apply_air_source_hvac_systems(model, runner, cooling_system, heating_system, sequential_cool_load_fracs, sequential_heat_load_fracs,
                                                                  weather.data.AnnualMaxDrybulb, weather.data.AnnualMinDrybulb,
-                                                                 conditioned_zone, @hvac_unavailable_periods)
+                                                                 conditioned_zone, @hvac_unavailable_periods, @schedules_file, @hpxml_bldg)
 
       elsif [HPXML::HVACTypeEvaporativeCooler].include? cooling_system.cooling_system_type
 
@@ -1648,9 +1648,9 @@ def add_heating_system(runner, model, weather, spaces, airloop_map)
       sys_id = heating_system.id
       if [HPXML::HVACTypeFurnace].include? heating_system.heating_system_type
 
-        airloop_map[sys_id] = HVAC.apply_air_source_hvac_systems(model, nil, heating_system, [0], sequential_heat_load_fracs,
+        airloop_map[sys_id] = HVAC.apply_air_source_hvac_systems(model, runner, nil, heating_system, [0], sequential_heat_load_fracs,
                                                                  weather.data.AnnualMaxDrybulb, weather.data.AnnualMinDrybulb,
-                                                                 conditioned_zone, @hvac_unavailable_periods)
+                                                                 conditioned_zone, @hvac_unavailable_periods, @schedules_file, @hpxml_bldg)
 
       elsif [HPXML::HVACTypeBoiler].include? heating_system.heating_system_type
 
@@ -1710,9 +1710,10 @@ def add_heat_pump(runner, model, weather, spaces, airloop_map)
              HPXML::HVACTypeHeatPumpMiniSplit,
              HPXML::HVACTypeHeatPumpPTHP,
              HPXML::HVACTypeHeatPumpRoom].include? heat_pump.heat_pump_type
-        airloop_map[sys_id] = HVAC.apply_air_source_hvac_systems(model, heat_pump, heat_pump, sequential_cool_load_fracs, sequential_heat_load_fracs,
+
+        airloop_map[sys_id] = HVAC.apply_air_source_hvac_systems(model, runner, heat_pump, heat_pump, sequential_cool_load_fracs, sequential_heat_load_fracs,
                                                                  weather.data.AnnualMaxDrybulb, weather.data.AnnualMinDrybulb,
-                                                                 conditioned_zone, @hvac_unavailable_periods)
+                                                                 conditioned_zone, @hvac_unavailable_periods, @schedules_file, @hpxml_bldg)
       elsif [HPXML::HVACTypeHeatPumpGroundToAir].include? heat_pump.heat_pump_type
 
         airloop_map[sys_id] = HVAC.apply_ground_to_air_heat_pump(model, runner, weather, heat_pump,