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System Loads and Sizing Reports

 
Six report types are available for loads and sizing:
·       Project and Climate
·       Plant Loops and Equipment
·       Space Loads and Ventilation
·       System Loads
·       Zone Loads
·       Room Loads
 
These new reports types are based around a single page PDF format, with report pages organized according to a linear scheme.  This means that, where applicable, the information pertaining to the building (as is the case in the Project and Climate report) or a system, zone or room (as it the case for the loads reports) are contained on a single page. This makes the interrogation of the reports quick, easy and effective.
In the case of the Loops & Equipment report or the Space Loads and Ventilation report the report may overlap onto multiple pages depending on the size of the project.
The header within each report references the report type (left hand side), the project name (center) and the VE version (right hand side). The following reports have additional information in the header:
 
·       Space Loads and Ventilation
The name of the system is displayed under the project name
 
·       System Loads Report
The name of the system is displayed under the project name
 
·       Zone Loads Report
The name of the zone is displayed under the project name and the parent system is displayed under the report type
 
·       Room Loads Report
The name of the room is displayed under the project name and the parent system and parent zone (if applicable) is displayed under the report type
 
In each report the notes to the LHS of the footer contains the following information:
·       Results file name
·       Date and time of generation
·       Reference to the report type
·       Page number relative to the total pages for that report type
 
Notes specific to the report type are contained on the RHS of the footer.
For all reports where data is not available or applicable a dash (-) is used.
 
Project and Climate
The project and climate report is the first report to be displayed unless it is unchecked. It shows a breakdown of model, location, weather and calculation data for the selected results file as well as giving a project loads summary. It is a single page report generated for each results file. It contains the following six frames:
·       Model Data
·       Location Data
·       Design Weather Data
·       Heating Calculation Data
·       Cooling Calculation Data
·       Project Loads Summary
 
Figure 5 - 1 : Project and Climate report page
 
Model Data:
The model data frame contains the following information:
 
Data label
Data source
Project file
The project .mit file name
HVAC file
The project .asp file used to generate the report
Model floor area
Total building floor area
Building floor area
Building conditioned floor area
Building Volume
Building conditioned volume
Number of conditioned rooms
Total number of rooms served by a system
Load analysis methodology
ASHRAE Heat Balance Method as per Apache Loads
Calculated
Date and time of calculation
Version No.
IESVE Version Number
 
Location Data:
The location data frame contains the following information:
Data label
Data source
Location
Taken from the ‘location & Site Data’ tab in ApLocate
Latitude
Taken from the ‘location & Site Data’ tab in ApLocate
Longitude
Taken from the ‘location & Site Data’ tab in ApLocate
Altitude
Taken from the ‘location & Site Data’ tab in ApLocate
Time Zone
Taken from the ‘location & Site Data’ tab in ApLocate
 
Design Weather Data:
The design weather data frame contains the following information:
Data label
Data source
Source
Taken from the ‘Design Weather Data’ tab in ApLocate
Monthly percentile - heating
Taken from the ‘Design Weather Data’ tab in ApLocate
Monthly percentile - cooling
Taken from the ‘Design Weather Data’ tab in ApLocate
Barometric pressure
This is atmospheric pressure taken from the design weather data
Air density
Taken from the ‘location & Site Data’ tab in ApLocate. This is one of the following:
·       Standard value which is the same for all locations (default)
·       Custom value which can be entered by the user
·       Derived value. Here the user can enter elevation and reference dry bulb and relative humidity values to derive the air density
Air specific heat
Constant value of 1019J/kgK in SI and 0.7886 Btu/lb·°F in IP
Density-spec heat product
Product of air density and specific heat
Summer Ground reflectance
Taken from the ‘location & Site Data’ tab in ApLocate
Winter Ground reflectance
Taken from the ‘location & Site Data’ tab in ApLocate
Carbon dioxide (ambient)
Taken from the ‘location & Site Data’ tab in ApLocate
 
Heating Calculation Data:
The heating calculation data frame contains the following information:
Data label
Data source
Results file
Name of associated .htn file
Calculated
Date and time of calculation
Profile Month
Taken from Apache System Loads settings
Outdoor winter design temp
Taken from the ‘Design Weather Data’ tab in ApLocate
 
Cooling Calculation Data:
The cooling calculation data frame contains the following information:
Data label
Data source
Results file
Name of associated .cln file
Calculated
Date and time of calculation
Profile Month
Taken from Apache System Loads settings
Max. outdoor temp dry bulb
Taken from the ‘Design Weather Data’ tab in ApLocate
Max. outdoor temp wet bulb
Taken from the ‘Design Weather Data’ tab in ApLocate
 
Project Loads Summary Data:
The project loads summary data frame contains the following information:
Data label
Data source
Cooling loads peak
This is the cooling design load peak taken from the System Parameters dialog for all active systems and summed to give the project cooling load peak. Note that this may potentially be a non-coincident peak if the systems are loaded at differing times.
Cooling load density
This is the cooling design load density associated with the peak shown above.
Heating loads peak
This is the heating design load peak taken from the System Parameters dialog for all active systems and summed to give the project heating load peak. Note that this may potentially be a non-coincident peak if the systems are loaded at differing times.
Heating load density
This is the heating design load density associated with the peak shown above.
 
Plant Loops and Equipment
The plant loops and equipment report is the second report to be displayed unless it is unchecked. It shows a breakdown of the water loops and equipment in the selected results file.  It can flow onto multiple pages if the HVAC file contains many water loops. This report contains details for the following three water loop types:
·       Chilled water loop;
·       Hot water loop;
·       Heat transfer loop
 
Only active loops are displayed in the report.
 
The data for each loop is contained within a single frame, which is named after the loop type and is numbered relative to the total amount of loops in the results file of that type.
Figure 5 - 2 : Plant Loops and Equipment report page
 
Chilled Water Loop:
The chilled water loop frame contains the following information:
Data label
Data source
Name
Chilled water loop reference name from the .asp file
Cooling capacity
Chilled water loop capacity from the .asp file
Primary design flow rate
Chilled water loop primary flow rate from the .asp file
Primary pump power
Chilled water loop primary flow rate multiplied by the relevant specific pump power, both from the .asp file
Secondary design flow rate
Here the capacity for each coil on the secondary loop is summed and the flowrate is calculated using the loop temperature difference
Secondary pump power
This is the flow rate calculated above multiplied by the relevant specific pump power
Condenser loop design capacity
Condenser water loop heat rejection capacity taken from the .asp file
Condenser loop design flow rate
Condenser water loop flow rate taken from the .asp file
Condenser loop pump power
Condenser water loop flow rate multiplied by condenser water loop specific pump power both taken from the .asp file
Pre-cooling loop capacity
Chilled water loop pre-cooling capacity taken from the .asp file
Equipment name and capacities - Chiller
Taken from the .asp file for each chiller:
Name: Reference name from the .asp file
Capacity: Design condition cooling capacity, Qdes
Equipment name and capacities – Cooling Tower
Taken from the .asp file
Name: Cooling tower (set label)
Capacity: Heat rejection, Qhrdes
Equipment name and capacities – Fluid cooler
Taken from the .asp file
Name: Fluid Cooler (set label)
Capacity: Heat rejection, Qhrdes
 
Hot Water Loop:
The hot water loop frame contains the following information:
Data label
Data source
Name
Hot water loop reference name from the .asp file
Heating capacity
Hot water loop capacity from the .asp file
Pre-heating condenser heat recovery capacity
Combination of two parameters - source multiplied by max heat recovery with HX. Source is the design capacity of either a specified part load chiller or condenser water loop. The HX parameters taken from the heat recovery dialog. Note if the user chooses an explicit heat transfer model, the calculation is source multiplied by heat exchanger design effectiveness. All parameters taken from the .asp file
Pre-heating water to water heat pump Capacity
As above but the calculation is extended due to the heat pump capacity rating i.e. Source multiplied by max. heat recovery with HX multiplied by heat pump capacity.
In the case of explicit heat transfer model the calculation is: Source multiplied by heat exchanger design effectiveness X heat pump capacity as a percentage of source loop capacity. All parameters taken from the .asp file
Pre-heating air to water heat pump capacity
Combination of two parameters - referenced air-to-water heat pump dialog output multiplied by the percent of auto sized heat source capacity. All parameters taken from the .asp file
Pre-heating combined heat & power capacity
This parameter comes from heat output in the CHP generator dialog
Primary design flow rate
Hot water loop primary flow rate from the .asp file
Primary pump power
Combination of two parameters - Hot water loop primary flow rate multiplied by the relevant specific pump power, both from the .asp file
Secondary design flow rate
Here the capacity for each coil on the secondary loop is summed and the flowrate is calculated using the loop temperature difference. Thus is then summed for all secondary loops
Secondary pump power
Combination of two parameters - Hot water loop secondary flow rate multiplied by the relevant specific pump power summed for all secondary loops
Equipment name and capacities - Boilers
Taken from the .asp file for each boiler:
Name: Reference name from the .asp file
Capacity: Design condition heating capacity, Qdes
 
Heat Transfer Loop:
The heat transfer loop frame contains the following information:
Data label
Data source
Name
Heat transfer loop reference name from the .asp file
Heating capacity
Heat transfer loop heating capacity from the .asp file
Cooling capacity
Heat transfer loop cooling capacity from the .asp file
Design flow rate
Heat transfer loop flowrate from the .asp file
Primary pump power
Combination of two parameters - flow rate multiplied by primary circuit specific pump power. All parameters taken from the .asp file
Secondary pump power
Combination of two parameters - flow rate multiplied by secondary circuit specific pump power. All parameters taken from the .asp file
Heat acquisition - condenser heat recovery capacity
As per condenser heat recovery for hot water loops
Heat acquisition – water to water heat pump capacity
As per WWHP for hot water loops
Heat acquisition – air to water heat pump capacity
As per AWHP for hot water loops
Heat acquisition – combined heat & power thermal capacity
As per CHP for hot water loops
Water-source heat exchanger  - heating capacity
Heat transfer loop water-source heat exchanger heating capacity from the .asp file
Water-source heat exchanger  - cooling capacity
Heat transfer loop water-source heat exchanger heating capacity from the .asp file
Heating equipment capacity - Boilers
Taken from the .asp file for each boiler:
Name: Reference name from the .asp file
Capacity: Design condition heating capacity, Qdes
Heat rejection equipment capacity – Cooling tower
Taken from the .asp file
Name: Cooling tower (set label)
Capacity: Heat rejection, Qhrdes
Heat rejection equipment capacity – Fluid cooler
Taken from the .asp file
Name: Fluid Cooler (set label)
Capacity: Heat rejection, Qhrdes
 
Space Loads and Ventilation
The space loads and ventilation report is the third report to be displayed unless it is unchecked. This report shows a high-level breakdown of the space loads and ventilation values for each system within the results file. It can flow onto multiple pages if the HVAC file contains more than one system.
The data shown in this table is consistent with that shown for the Zone Airflow Distribution table within ApacheHVAC, and thus includes only those spaces/zones assigned to Principal Room/Zone components. Therefore, the Space Loads and Ventilation report is a summary of loads for the Principal Room/Zone spaces on each system, and not a listing of coil loads, which might include additional loads for non-principal spaces, outdoor air ventilation, etc.
It should be noted that this table is populated via the ApacheHVAC .asp file either via the system loads run results (.cln file or .htn file) or the via the Room & Zone Loads run results (.clg or .htg file) depending on the level being reported.
The report also shows zone and room level loads and airflows. Zone loads are the coincident peak for all rooms in each zone, and are set by the Room & Zone Loads run. Zone airflows are the zone cooling and heating max airflows from the System Parameters UI. Room level loads data in the table are the non-coincident peak value from the Room & Zone Loads run for the room.
Both Room Loads and Zone Loads (the coincident peak for the rooms in each zone) in this report are populated from the System Parameters dialog and Zone Airflow Distribution table in the .asp file.  These values are typically generated from the Room & Zone loads analysis run––i.e., normally using ‘saturated’ gain profiles, without diversity factors, and before any influence from system operation and controls. 
System Loads in this report are coincident peak values from the System loads analysis run––i.e., normally using the same gain profiles and diversity factors as in the full dynamic simulation, and including the influences of system operation and controls.
One report is shown per system with the system name in the header. In the case of PTAC and Single Zone systems the name also includes a layer number for easier cross reference.
 
Figure 5 - 3 : Space Loads and Ventilation report page
 
 
 
 
System Level:
The following information is provided for the system:
Data label
Data source
Sensible Cooling Load
Coincident peak value from the System Loads run for all zones on the system
Latent Cooling Load
Coincident peak value from the System Loads run for all zones on the system
Total Cooling load (also provided per unit floor area)
Sum of the above
Cooling Airflow (also provided per unit floor area)
The system airflow peak from the System Loads run at the time of peak cooling load
Heating load (also provided per unit floor area)
Coincident peak value from the System Loads run for all zones on the system
Heating Airflow (also provided per unit floor area)
The system airflow peak from the System Loads run at the time of peak heating load
Outdoor Airflow Req. (also provided per unit floor area)
This is system minimum outdoor ventilation requirement before considering the possibility of a greater requirement for outside air to make up for total system exhaust airflow and is equivalent to Vot in the System Parameters UI
Min OA Airflow (also provided per unit floor area)
Minimum outdoor air from the System Loads run at cooling vs. heating peak times
 
 
 
Zone Level:
The following information is provided for each zone served by the system:
Data label
Data source
Sensible Cooling Load
Coincident peak value from the Room & Zone Loads run as recorded in the System Parameters dialog, subject to user edit, for all rooms in the zone
Latent Cooling Load
Coincident peak value from the Room & Zone Loads run as recorded in the System Parameters dialog, subject to user edit for all rooms in the zone
Total Cooling load (also provided per unit floor area)
Sum of the above
Cooling Airflow (also provided per unit floor area)
The Zone Cooling Max Airflow from the System Parameters UI
Heating load (also provided per unit floor area)
Coincident peak value from the Room & Zone Loads run as recorded in the System Parameters dialog, subject to user edit for all rooms in the zone
Heating Airflow (also provided per unit floor area)
The Zone Heating Max Airflow from the System Parameters UI
Outdoor Airflow Req. (also provided per unit floor area)
Zone Ventilation Max/Total Required from the System Parameters UI
Min OA Airflow (also provided per unit floor area)
Minimum outdoor air from the System Loads run at cooling vs. heating peak times
 
 
Figure 5 - 4 : Zone Airflow Distribution table showing a system 7a with completed system sizing and user edits (orange text) and a system 5b with completed room & zone level sizing, but without completed system sizing (blue text).  All autosized values appear in green text.
 
 
 
Room Level:
The following information is provided for each room served by the system:
Data label
Data source
Sensible Cooling Load
Peak value from the Room & Zone Loads run as recorded in the System Parameters dialog, subject to user edit for the room
Latent Cooling Load
Peak value from the Room & Zone Loads run as recorded in the System Parameters dialog, subject to user edit for the room
Total Cooling load (also provided per unit floor area)
Sum of the above
Cooling Airflow (also provided per unit floor area)
The Zone Cooling Max Airflow from the System Parameters UI multiplied by the room airflow apportioning factor (%) as per the Zone Airflow Distribution table.
Heating load (also provided per unit floor area)
Peak value from the Room & Zone Loads run for the room
Heating Airflow (also provided per unit floor area)
The Zone Heating Max Airflow from the System Parameters UI multiplied by the room airflow apportioning factor (%) as per the Zone Airflow Distribution table
 
Space Conditioning Loads Reports
The space conditioning loads reports show the breakdown of a system at three different levels across a series of single page reports. The three levels shown are
·       System
·       Zone
·       Room
If HVAC zones do not exist in the model then this report will not be available for generation. If they exist only for a select number of systems within the model then only the reports relevant to these systems will contain zone level reports.
System Loads, Zone Loads, and Room Loads values in this set of three reports are taken from the System loads analysis run at the time of the relevant peaking device or system load––i.e., normally using the same gain profiles and diversity factors as in the full dynamic simulation, and including the influences of system operation and controls.
These reports are thus focused on documenting contributions to system and coils loads and the differences between design airflow rates, ventilation requirements, and temperature and the actual values for these during the System loads analysis run with the system in operation.
The reports are split into three columns, which are further split into relevant frames within each column as follows:
 
 
 
Cooling
·       Cooling coil peak
This is the breakdown of all the gains and losses contributing to the peak coil load (as selected in the report generator settings)
·       System/Zone/Room peak
This is an equivalent breakdown at the system/zone/room peak time depending on the report level
·       Cooling coils and room units
This shows peak performance information of associated coils and room units relevant to the report level
 
Heating
·       Heating coil peak
This is the breakdown of all the gains and losses contributing to the peak coil load (as selected in the report generator settings)
·       Heating coils and room units
This shows peak performance information of associated coils and room units relevant to the report level
 
Supplementary information
·       Areas
Areas served by the system broken down cross all three levels
·       Temperatures
System temperatures relevant to the level
·       Airflow
System airflows relevant to the level
·       Checks
System checks relevant to the level
 
The following images show an example of a system, zone and room loads report.
 
Figure 5 - 5 : System Loads report page
 
 
Figure 5 - 6 : Zone Loads report page
 
Figure 5 - 7 : Room Loads report page
 
 
 
Cooling Coil Peak
 
Figure 5 - 8 : Cooling Coil Peak section of System, Zone, and Loads report pages
 
This frame itemizes gains contributing to the load on a cooling coil at a peak time associated with the peaking device as selected in the report generator settings. The name of this frame is dynamic and will update depending on the peaking device selected.
This frame is broken down across the series of rows and columns, which are detailed as follows:
 
 
 
 
 
Rows (reported gain classes):
·       Envelope Gains/Losses
These are the gains/losses associated with the envelope e.g. external walls, roofs, solar, ventilation associated with the envelope, etc.
·       Internal Building Gains/Losses
These the gains/losses associated with the internal structures and other gain/losses from exchange between neighbouring elements like duct leakage, conduction and non-principle spaces
·       Internal Gains
These the gains/losses associated with internal contributions within the room/zone e.g. lights, people, equipment
·       Mechanical Gains/Losses
These are gains/losses associated with mechanical elements within the system itself
 
Columns:
·       Zone/Room
These are the gains/losses associated with the room or zone itself (aggregated at system and zone level as appropriate)
·       RA Plenum
The RA Plenum column lists the gains/losses associated with the particular Room/Zone at hand accruing directly to the RA Plenum (or a portion of such gains where the plenum is shared). These gains include, for example, Lighting Gains fraction to plenum for lights in that particular Room/Zone, Supply Air Leakage and Duct Heat Gain/Loss
·       Net Value
These are the gains/losses that directly contribute to the coil load and in most cases are a sum of the system/zone/room column and the plenum column. However, there are exceptions, which will be detailed below.
·       Percent of total
Displays, for each row, the value in the adjacent ‘Net Value’ column expressed as a percentage of the total appearing at the bottom of that column (or a dash if the ‘Net Value’ column contains a dash).
 
Where appropriate the room level gains/losses are aggregated to zone level and to system level.
The peak time of the selected peaking device is shown at the top of this frame along with the outside air dry bulb (DB), outside air wet bulb (WB) and the outside air relative humidity (RH) at that time.
 
Envelope Gains/Losses:
Data label
Data source
External Walls
Conduction gain - external wall from the .cln file
Roofs
Conduction gain – roof from the .cln file
Ground/Exposed Floors
Conduction gain - ground floor from the .cln file
External Doors
Conduction gain – external doors from the .cln file
Windows Conduction
Conduction gain - external glazing from the .cln file
Skylight Conduction
Conduction gain – rooflights from the .cln file
Solar
Solar gain from the .cln file
Infiltration
Infiltration gain from the .cln file
Nat/Aux Vent
Natural vent gain + Aux mech vent gain from the .cln file
 
Internal Building Gains/Losses:
Data label
Data source
Internal Walls/ Openings
Conduction gain - internal wall  +  Conduction gain - internal door + Conduction gain - internal glazed from the .cln file
Internal Floors/Air/Furn.
Conduction gain – floor  + Air & furniture dynamic gain from the .cln file
Ceilings
Conduction gain – ceiling   from the .cln file
Duct Conduction
Duct conduction gain from the .cln file. This contributes to the Net Total column. If the duct is contained within the same control volume (i.e., within the subject conditioned space), the space gain will be cancelled by an equal loss reported on the SA Duct (conduction) line in mechanical gains/losses
Duct Leakage †
 
Duct leakage sensible gain from the .cln file. This reports the gain to subject space in Room/Zone column and gain to RA Plenum serving the subject space in the RA Plenum column where appropriate depending on the leakage configuration in the HVAC file.
As designated by the dagger, duct Leakage gain does not contribute to the Net Value column because it is either internal to the control volume or already included in the ventilation gain terms.
Note: not to be confused with ‘SA Duct Leakage’ in Mechanical Gains/Losses section.
Non-Principal Spaces
This is the sensible gains (other than mechanical ventilation gains) to voids and zones/rooms other than principal zones/rooms and their associated plenums. Calculated from the flowrate into and the temperature across the non-principle space. Any duct leakage sensible gain is deducted from this figure
 
Internal Gains:
Data label
Data source
Lights
Lighting gain from the .cln file
People
People gain from the .cln file
Misc,Computers,Equip
Equipment gain from the .cln file
 
The budget method makes use of known quantities to determine unknown ones in air flow networks. It describes a system as a control volume which has inlets and outlets. Net mass flow into a control volume is zero (that is, outflow is balanced with inflow). Heat flowing into and out of a control volume is tracked by noting the inlet and outlet temperatures. In addition to the heat flowing into and out of the control volume, all gains are tracked within the volume. Unknown gains can be determined via difference based upon these known heat flows.
Mechanical Gains/Losses:
Data label
Data source
Ventilation (sensible)
This is the net sensible heat added to the system by mechanical ventilation.
 
At zone level it is apportioned to the zone based on the proportion of sensible gains in the multiplex layer (all envelope, internal, non-principle, mechanical and the subject coil if it’s in the multiplex) compared to the sum of the gains for all layers.
 
At room level it is apportioned based on the airflow percentages from the Zone Airflow Distribution table (ZAD).
Transfer Air †
This is the gain attributable to the intake of air drawn from other spaces. As designated by the dagger symbol ( † ), Transfer Air is not reported in the Net Value column, as it is moving air and thus loads around within the scope of the peaking system coil loads.
 
The contribution is calculated from the transfer air parameters (flow, transfer air temperature and room cooling setpoint) set in the relevant layer of the relevant system.
SA Duct Leakage †
This is the gain attributable to the additional load resulting from air leakage from supply ducts. As designated by the dagger, this is not reported in the Net Value column. If the peaking device is at zone or room level this parameter is not reported as contribution to supply air is assumed to be upstream of the zone coil.
 
The contribution is calculated from the leakage parameters (leakage %, flow, supply air temperature and room cooling setpoint) set in the relevant layer of the relevant system.
Fans
This is the heat gain from fans i.e. sensible gains from fans in the zone/room multiplex layer, plus a portion of gains from fans at system level all apportioned and aggregated.
 
The contribution is calculated from the fan parameters i.e. flow and temperature difference across the fan.
SA Duct (conduction)
This is the conduction heat gain to ducts (and thus to supply air on route to the subject space). This gain represents a transfer of heat to the system from a space (possibly the exterior space). If that space is in the same system, or the same zone, it will be balanced in the system or zone account by an equal loss from that space (part of the space’s ‘Duct conduction’ gain, see above). If the space is exterior or in a different system, the gain constitutes a net gain to the control volume.
 
The sensible gain is calculated from the temperature difference across the duct component and the mass flow entering it, as leakage is assumed to occur at the duct outlet.
Supply Air Plenum
This is the sensible gain to the supply air plenum if one exists.
 
The gain is calculated from flow and temperature difference characteristics (accounting for the duct conduction gain) as well as accounting for any leakage.
Room Units, Coils, etc.
Sensible gain from eligible components, other than the peaking device, in the zone/room multiplex layer, plus a portion of gains from components at the system level all apportioned and aggregated.
 
Eligible components are room units, Monodraught heater batteries, heating and cooling coils, Colorcoat Renew solar collectors, spray humidifiers (negative gain) and steam humidifiers (positive gain) and ducts.
Latent Cooling
The latent load on the cooling coil, taken the component output variable in the .cln file
Dehumid Oversizing †
This parameter is intended to report the additional coil capacity resulting specifically from the cooling of the supply air, as driven by system or zone setpoints for max RH, to a temperature below the SAT required for sensible space cooling, which is then followed immediately by reheating of the supply airflow to the SAT for space cooling. This added capacity for dehum followed by reheat (which may be accomplished by a  heat pipe, runaround coil, or similar means between the AHU cooling and heating coils, with the heating coil as backup) is required to avoid overcooling any space already at min airflow as an unintended consequence of controlling humidity.
 
This should not be confused with the Latent Cooling parameter above. This is essentially AHU reheat load (reheat by AHU heating coil or other device immediately after the AHU cooling coil). This should be permitted only for sub-cooling the supply air to satisfy dehumidification requirements, as it would otherwise be a pointless waste of cooling and heating energy.
 
As designated by the dagger, this is not reported in the Net Value column.
 
In the case of plenums, for a principal room (in a Room Loads Report) or a principal zone (in a Zone Loads Report) which has a dedicated RA plenum in the same multiplex layer, the ‘RA Plenum’ column lists, in each row, the total gain to the RA plenum.
For a room which forms part of a zone with a dedicated RA plenum in the same multiplex layer, the ‘RA Plenum’ column lists, in each row, a portion of the total gain to the RA plenum. In this case the gain is distributed among the rooms for reporting purposes in the usual proportions (based on air supply to the rooms), with the exception that any lighting gain via light fittings is apportioned to the room from which it originates.
For a principal room (in a Room Loads Report) or a principal zone (in a Zone Loads Report) which shares an RA plenum with other principal rooms or zones in the same multiplex the gains are distributed as per the apportioning logic for the room/zone column.
For a System Report, the RA Plenum column lists the total gains accruing directly to RA Plenums associated with all principal rooms or zones in the system.
Note: any spaces - including RA plenums – that are not in a multiplex do not generate gains in the ‘RA Plenum’ column. Their gains contribute to ‘Non-Principal Spaces’ gains for the air handling system.
Cooling System/Zone/Room Peak
Figure 5 - 9 : Cooling System/Zone/Room Peak section of System, Zone, and Loads report pages
 
This section  is headed ‘Room Peak’ in Room Loads Reports, ‘Zone Peak’ in Zone Loads Reports and ‘System Peak’ in System Loads Reports. It itemizes gains (reported gain classes) to a room or zone (or a set of rooms or zones in the case of a System Loads Report) at the time of peak room cooling. This is defined as when the variable ‘Space conditioning sensible’ for the subject room (or in the case of Zone and System Loads Reports multiple rooms or zones) totaled over all the relevant rooms or zones, is at its maximum negative value.
The derivations of entries in this part of the report (under the column headings ‘Room’ and ‘Percent of Total’) follow the same procedures as those in the ‘... COOLING ... PEAK’ section, with the following exceptions:
·       Mechanical Gains/Losses – these do not apply and are reported as dashes (–).
·       Values in the ‘Percent of Total’ column refer to the adjacent values in the ‘(Sensible)’ column.
 
Heating Coil Peak
Figure 5 - 10 : Heating Coil Peak section of System, Zone, and Loads report pages
 
This section itemizes gains (reported gain classes) contributing to the load on a heating coil or other heating device at a peak time specified in the report generator settings. As with the cooing coil peak, this determines the wording of the header.
The derivations of entries in this part of the report (under the headings ‘Room’ (or ‘Zone’) ‘RA Plenum’ and ‘Net Total’) follow the same procedures as those in the cooling coil peak section, with the following exceptions:
 
 
 
·       Inputs are taken from the .htn file rather than the .cln file.
·       So long as the ‘Default’ box is checked in the Heating Loads section of the ASHRAE Loads dialog, the ‘Time of peak’ on the report shall display ‘Heating Design’.
·       Setpoints are used in the calculation of some of the mechanical gains/losses, in this case these are heating setpoints rather than cooling setpoints.
·       The rows for Latent Cooling Load and Dehumid Oversizing are not relevant and therefore are omitted
 
Cooling Coils and Room Units
 
Figure 5 - 11 : Cooling Coils and Room Units section of System, Zone, and Loads report pages
 
This frame shows the design values for the cooling coils and cooling room units in the system. Devices at system level are shown on the system report and their proportional contribution at zone and room level are shown on those reports. Devices at zone level are shown on the zone report and their proportional contribution at room level is shown on the room level report.
The following cooling devices are reported:
·       System cooling coil
·       Ventilation cooling coil
·       Indirect and direct evaporative cooling
·       FCU, FPB or Active beam
·       Room units. In this case only the capacity and entering/leaving water temperatures are shown
 
The oversizing toggle affects the capacities displayed in this frame and a note directly under the frame indicates if oversizing has been included or not.
 
 
 
 
 
Data label
Data source
Total Capacity
This is the total capacity taken from the .asp file. In the case of evaporative cooling this is calculated from conditions in the .cln file
Sensible Capacity
This is the sensible capacity. The proportion of total to sensible is obtained from the .cln file and this is then applied to the total from the .asp to get the design sensible capacity
Airflow
This is the airflow from the .asp file. When the .asp is not a valid source it is taken from the .cln file
Entering DB/WB/RH
This is the entering conditions from the .asp file. When the .asp is not a valid source the values are taken from the .cln file
Leaving DB/WB/RH
This is the leaving conditions from the .asp file. When the .asp is not a valid source the values are taken from the .cln file
 
Heating Coils and Room Units
 
Figure 5 - 12 : Heating Coils and Room Units section of System, Zone, and Loads report pages
 
This frame shows the design values for the heating coils and heating room units in the system. Devices at system level are shown on the system report and their proportional contribution at zone and room level are shown on those reports. Devices at zone level are shown on the zone report and their proportional contribution at room level is shown on the room level report.
The following heating devices are reported:
·       System heating coil
·       Ventilation heating coil
·       Pre-heat coil
·       Re-heat coil
·       FCU, FPB or Active beam
·       Room units. In this case only the capacity and entering/leaving water temperatures are shown
 
The oversizing toggle affects the capacities displayed in this frame and the same note referenced in the cooling coil and room units frame indicates if oversizing has been included or not.
 
Data label
Data source
Total Capacity
This is the total capacity taken from the .asp file
Airflow
This is the airflow from the .asp file. When the .asp is not a valid source it is taken from the .htn file
Entering DB
This is the entering dry bulb from the .asp file. When the .asp is not a valid source the values are taken from the .htn file
Leaving DB
This is the leaving dry bulb from the .asp file. When the .asp is not a valid source the values are taken from the .htn file
 
Areas
 
Figure 5 - 13 : Areas section of System, Zone, and Loads report pages
 
This frame details the gross surface areas of the zones or rooms served by the system. These are then summed to give the areas at system level. The frame also outlines the glazing area in the relevant surfaces and shows this as a percentage.
 
 
Data label
Data source
Wall
External wall area + external glazing area (excluding doors and holes)
 
External glass area in associated wall as area and percentage of gross wall area
Roof
External roof area + external skylight area (excluding holes)
 
External skylight area in associated roof as area and percentage of gross roof area
External Floor
Area of ground and exposed floors
Door
External door area
Partition/Door
Internal vertical partition and door area (including glazing & holes)
Internal Ceiling
Internal ceiling area
Internal Floor
Internal floor area
 
Temperatures
 
Figure 5 - 14 : Temperatures section of System, Zone, and Loads report pages
 
 
This frame reports relevant temperatures at system, zone and room level. The parameters change depending on the reporting level.
 
 
System level:
Note, where appropriate the data source is at the time of peak system cooling and heating loads, respectively (coincident peak value for all zones on the system).
 
Data label
Data source
Supply air (design)
This is the system level design temperature and is obtained from the systems parameters UI for heating and cooling as follows:
 
  • If a Packaged terminal unit or single zone this is taken from the ‘Zone loads & airflows tab’ (cooling and heating design zone air temperatures)
  • If a non-DOAS system this is taken from the System Parameters dialog in SP. (Cooling - ‘System min SAT for space cooling & vent tempering’, Heating - ‘Heating mode max SAT’)
  • If DOAS then it references ‘DOAS ventilation air tempering max SAT (subject to SAT reset) for cooling and ‘DOAS ventilation air tempering min SAT’ for heating.
Supply air (actual)
The actual system supply temperature is obtained from the .cln and .htn respectively. This is determined by querying the following nodes:
 
  • Packaged and single zone systems: node entering the room/zone
  • All other system: node just before the multiplex boundary
Return air (actual)
The actual system return temperature is obtained from the .cln and .htn respectively. This is determined by querying the following nodes:
 
  • Packaged and single zone systems: node leaving the room/zone
  • All other system: node to the RHS of the RA damper
Plenum (actual)
Not applicable at system level therefore is shown as a dash (-)
Mixed air (actual)
The actual system mixing temperature is taken from the .cln and .htn and references the mixing damper outlet node.
Fan Motor Temp Rise (dT)
This is the temperature rise due to the motor and is given by:
 
 
 
Where,
   - is the total fan power at time of peak flowrate .
 
 - is the motor efficiency at peak flow rate ,
 
 and  - are the reference air density and specific heat capacity of air respectively
Fan Blade Temp Rise (dT)
This is the heat rise due to the fan (everything that isn’t the motor and the drive mechanism) and is given by:
 
.
 
Where -  is determined by querying the node either side of the system level fan
Fan Configuration
This is determined based on the relative location of the system cooling coil and the supply fan, see section Error! Reference source not found. for further information
 
Zone level:
Note, where appropriate the data source is at the time of peak zone cooling and heating loads, respectively (coincident peak value for all rooms in each zone).
Data label
Data source
Supply air (design)
This is the zone level design temperature and is obtained from the system parameters UI for heating and cooling (‘Zone loads & airflows tab’ - cooling and heating design zone air temperatures)
Supply air (actual)
The actual zone supply temperature is obtained from the .cln and .htn. This is determined by querying the node entering the zone
Return air (actual)
The actual zone return temperature is obtained from the .cln and .htn. This is determined by querying the node leaving the zone
Plenum (actual)
This is the actual plenum temperature obtained from the .cln and .htn. This is determined by querying the node directly downstream of the plenum component
Mixed air (actual)
Same as the system mixing temperature
Zone Fan Temp Rise (dT)
This parameter is shown only when there is a zone-level fan, such as in a fan-coil unit or FPB.
 
At zone level the reports show the complete fan temp rise which is obtained from the .cln and .htn file
 
 
 
Room level:
Note, where appropriate the data source is at the time of peak room cooling and heating loads, respectively.
Data label
Data source
Supply air (design)
This is the room level design temperature and is obtained from the systems parameters UI for heating and cooling (‘Zone loads & airflows tab’ - cooling and heating design zone air temperatures). Note that for rooms in zones, this is the same for each room.
Supply air (actual)
The actual room supply temperature is obtained from the .cln and .htn.  This is determined by querying the node entering the room. Note that for rooms in zones, this is the same for each room.
Room Setpoint (design)
This is obtained from the ‘Systems Schedules and Setpoints’ dialog
Room throttling range
This is currently blank (not reported) and may be included in future versions
Room (actual)
The room temperature is obtained from the .cln and .htn
Return air (actual)
The actual room return temperature is obtained from the .cln and .htn.  This is determined by querying the node leaving the room. Note that for rooms in zones, this is the same for each room.
Plenum (actual)
This is the actual plenum temperature obtained from the .cln and .htn. This is determined by querying the node directly downstream of the plenum component. Note that for rooms in zones, this is the same for each room.
Mixed air (actual)
Same as the system mixing temperature
Zone Fan Temp Rise (dT)
This parameter is shown only when there is a room-level fan, such as in a fan-coil unit or FPB.
 
This is not applicable for rooms in zones and is therefore a dash (-). At room level the reports show the complete fan temp rise which is obtained from the .cln and .htn file.
 
 
 
 
Airflow
Figure 5 - 15 : Airflow section of System, Zone, and Loads report pages
 
This frame reports relevant airflows at system, zone and room level. The parameters change depending on the reporting level.
 
 
 
System level:
Note, where appropriate the data source is at the time of peak system cooling and heating loads, respectively (coincident peak value for all zones on the system).
 
Data label
Data source
Supply (design)
This is the system level design airflow and is obtained from the system parameters UI for heating and cooling (‘Zone loads & Supply Airflows tab’ for package and single zone systems or ‘System supply fan design flow rate, Vpsd’ for all other systems)
Supply (actual)
The actual system supply airflow is obtained from the .cln and .htn respectively. This is determined by querying the following nodes:
 
  • Packaged and single zone systems: node entering the room/zone
  • All other systems: node just before the multiplex boundary
 
These will normally be coincident with the time system-level coincident peak cooling and heating loads for all zones, respectively. There are certain cases for particular systems, control schemes, and climates, however, wherein the greatest system airflow in either Cooling or Heating mode will be required at a point in time that does not coincide with the peak loads for one or both of these operating modes. The reported values will always be the maximum airflow recorded during the Cooling and Heating design sizing runs, respectively, regardless of coincidence with peak loads
Reheat Minimum (design)
This is the minimum primary airflow for each zone, obtained from the system parameters UI, summed to get the system value
Leakage at Design Flow
This is the zone leakage airflow, which is obtained by multiplying the percentage leakage by the zone supply design flow and summed to get the system value. If the leakage occurs at system level then this is calculated with system values.
Return (actual)
The actual system return airflow is obtained from the .cln and .htn respectively . This is determined by querying the following nodes:
 
  • Packaged and single zone systems: node leaving the room/zone
  • All other system: node to the RHS of the RA damper
Exhaust and Relief (actual)
This is the flow out of all the system outlets summed
Ventilation (requirement)
This is the system ventilation requirement and is taken from the System Parameters dialog (‘System minimum outdoor air intake, ‘Vot/make-up’)
Ventilation (actual)
This is the actual system ventilation and is obtained from the .cln and .htn respectively. The source of this data varies depending on the system configuration i.e.
 
  • DOAS - Heat recovery bypass damper outlet if present, else the system air inlet
  • Package terminal unit and single zone - M ultiplex boundary node for incoming outdoor air supply. The ‘system’ in this case is the same as the zone. There may not be an actual ‘inlet’ component if the user has coupled the PTAC/PTHP inlet to another system
  • Mixing Systems - Flow rate at heat recovery bypass damper outlet if present, else OA Economizer damper inlet if present
 
Note that a flag has been provided to indicate DCV. This uses dynamic text to append ‘– DCV’ to the ‘Ventilation (actual)’ label, so that this would read ‘Ventilation (actual) – DCV’ for any system with DCV
Infiltration
The infiltration rate for all room/zones is obtained from the .cln and .htn and summed to give the system level value
 
 
 
Zone level:
Note, where appropriate the data source is at the time of peak zone cooling and heating loads, respectively (coincident peak value for all rooms in each zone)
Data label
Data source
Supply (design)
This is the zone level design airflow and is obtained from the system parameters UI for heating and cooling. (‘Zone loads & Supply Airflows tab’)
Supply (actual)
This is the actual system supply airflow into the zone and is obtained from the .cln and .htn. This is determined by querying the node entering the zone
Reheat Minimum (design)
This is the minimum primary airflow for the zone, obtained from the system parameters UI
Leakage at Design Flow
This is the zone leakage airflow and is obtained by multiplying the percentage leakage by the supply design flow
Return (actual)
This is the actual zone return airflow and is obtained from the .cln and .htn . This is determined by querying the node leaving the zone
Exhaust (actual)
This is the flow on the zone exhaust path obtained from the .cln and .htn respectively
Ventilation (requirement)
This is the zone ventilation requirement and is taken from the system parameters dialog (‘Max req.’ from the ‘Zone Ventilation & Exhaust’ tab)
Ventilation (actual)
This is the actual zone ventilation and is obtained from the .cln and .htn respectively. The source of this data varies depending on the system configuration i.e.
 
  • DOAS - Flow at node for controller with ‘DOAS Vent Airflow’ or ‘DOAS Vent Airflow CAV/DCV’ link
  • Package terminal unit and single zone - Flow rate at multiplex boundary node for incoming outdoor air supply. This may not be an actual ‘inlet’ component if the user has coupled the PTAC/PTHP inlet to another system
  • Mixing Systems - Flow is determined by determining the system OA fraction (OA flow rate system level divided by total system supply flow rate). This is then multiplied by the zone supply (actual) peak airflow to get the ventilation actual flow to the zone
 
Note that a flag has been provided to indicate DCV. This uses dynamic text to append ‘– DCV’ to the ‘Ventilation (actual)’ label, so that this would read ‘Ventilation (actual) – DCV’ for any system with DCV
Infiltration
This is the infiltration rate for the zone and is obtained from the .cln and .htn
 
 
 
Room level:
Note, where appropriate the data source is at the time of peak room cooling and heating loads, respectively. In addition, for rooms in zones the zone flow is distributed among the rooms as per the proportioning in the zone airflow distribution table (ZAD)
Data label
Data source
Supply (design)
This is the room level design airflow and is obtained from the system parameters UI for heating and cooling. (‘Zone loads & Supply Airflows tab’)
Supply (actual)
This is the actual system supply airflow into the room and is obtained from the .cln and .htn. This is determined by querying the node entering the room
Reheat Minimum (design)
This is the minimum primary airflow for the room, obtained from the system parameters UI
Leakage at Design Flow
This is the room leakage airflow and is obtained by multiplying the percentage leakage by the supply design flow.
Return (actual)
This is the actual room return airflow and is obtained from the .cln and .htn . This is determined by querying the node leaving the room
Exhaust (actual)
This is the flow on the room exhaust path obtained from the .cln and .htn respectively
Ventilation (requirement)
This is the room ventilation requirement and is taken from the system parameters dialog (‘Max req.’ from the ‘Zone Ventilation & Exhaust’ tab).
Ventilation (actual)
This is the actual room ventilation and is obtained from the .cln and .htn respectively. The source of this is the same as for zones.
Infiltration
This is the infiltration rate for the room and is obtained from the .cln and .htn
 
 
 
 
Checks
Figure 5 - 16 : Checks section of System, Zone, and Loads report pages
 
This frame provides a series of engineering checks, which can be used to verify performance at system, zone and room level. Most of these checks already exist in the system parameters UI and are sourced from there.
 
Data label
Data source
Number of people
Sourced from the system parameters UI for each zone and summed to get the value at system level. (Zone airflow, turndown & engineering checks tab).
 
In the case of rooms within zones the value is taken directly from the room.
ft2/person
Sourced from the system parameters UI for each zone (Zone airflow, turndown & engineering checks tab).  This data is then used to calculate system level value.
 
In the case of rooms within zones the value is calculated directly from room parameters (room floor area and peak occupancy)
Btu/hr.ft2 – Cooling & Heating
Sourced from the system parameters UI for each zone (Zone airflow, turndown & engineering checks tab). This data is then used to calculate system level value.
 
In the case of rooms within zones the value is calculated directly from room parameters (room load from the Zone Airflow Distribution table (ZAD) and room floor area)
ft2/ton – Cooling & Heating
Sourced from the system parameters UI for each zone (Zone airflow, turndown & engineering checks tab). This data is then used to calculate system level value.
 
In the case of rooms within zones the value is calculated directly from room parameters (room load from the Zone Airflow Distribution table (ZAD) and room floor area)
cfm/ft2 – Cooling & Heating
Sourced from the system parameters UI for each zone (Zone airflow, turndown & engineering checks tab). This data is then used to calculate system level value.
 
In the case of rooms within zones the value is calculated directly from room parameters (room airflow from the Zone Airflow Distribution table (ZAD) and room floor area)
% Outdoor Air - Cooling & Heating
Sourced from the system parameters UI for both zone and system level (Zone airflow, turndown & engineering checks tab).
 
At room level the necessary parameters required to calculate % outdoor air are taken from the Zone Airflow Distribution table (ZAD) (ventilation and room airflow)
Outdoor air cfm/ft2
Sourced from the system parameters UI for system level (Zone airflow, turndown & engineering checks tab).
 
At zone and room level the outdoor air flow is taken from the Zone Airflow Distribution table (ZAD) (ventilation airflow) and along with floor area is used to calculate the required values.
Outdoor air cfm/person
Sourced from the system parameters UI for system level (Zone airflow, turndown & engineering checks tab).
 
At zone and room level the outdoor air flow is taken from the Zone Airflow Distribution table (ZAD) (ventilation airflow) and along with No. of people is used to calculate the required values.
Peak latent Load (Btu/h)
This value is determined based on the peak Latent Load at the system cooling coil (independent of the overall cooling coil peak) and is distributed out to the zone and room as per the proportioning in the Zone Airflow Distribution table (ZAD)