Release Notes
- Yannick Motton (Unlicensed)
- tom@hysopt.com
- Joa Oris
Welcome to the official Release Notes of the Hysopt product portfolio. This page gives you a concise overview of all updates to the Hysopt product portfolio.
If an update is only applicable to a specific Hysopt product, the update is marked with the corresponding product label (e.g. Simulator-only, Calculator-only ).
All other updates are general software improvements available to all users.
For the Hysopt BIM Syncer, updates marked with 🔄️ require an update of the revit plug-in. This newest revit plug-in can be downloaded here.
Changes Mar 5, 2025
Added recent model access in the Hysopt model explorer
A left ribbon is added to the Hysopt model explorer for quick access features
The recent models list allows you to quickly open one of 10 most recent models
You can also quick-navigate to the folder of a recent model using
Input (I) & Output (O) control connectors are now visually distinct Simulator-only
You can now easily differentiate control inputs from control outputs at a glance
Input control connectors are now lightgrey and annotated with an “I”
Output control connectors are darkgrey and annotated with an “O”
Save reminder settings are now adjustable under user preferences, see User Preferences 
You can adjust the time interval inbetween save reminders, or completely deactivate the functionality
Upgraded PICV model for enhanced simulation behaviour
The upgraded PICV model ensures that “Actual Flow Rates” are now more accurately calculated
Minimal impact on existing models expected (< 3% volume flow rate changes at PICVs)
Changes Feb 19, 2025
Introducing a save reminder (30 Min.) to avoid losing recent changes
The save reminder prevents potential data loss from an unexpected system/browser crash
Introducing Pressure Drop in Design by default in the Hysopt library Calculator-Only
Pressure Drop in Design is now default when selecting a Base Circuit from the Hysopt library
Hereby, Pressure Drop in Design replaces Kv values.
Improved hydraulic calculations of the generic HIU Base Circuits Calculator-Only
The updated calculations have a limited impact on the output of
Optimise components in existing models
Small UI changes and general bug fixes
Mouse now exactly follows a node whilst dragging
Improved usability of the Kv value input help calculator Calculator-only
Advanced view is deactivated by default for new users
Changes Feb 5, 2025
Canvas link highlighting when navigating between links (Ctrl+Click)
Ctrl+Click on a canvas link will now combine “navigation to” and “highlight” the end link
Allows to quickly identify the arrival node of any canvas link connection
Pressure drop in design introduced in the snippet library
All input Kv values will be pre-configured to pressure drop in design parameters in all snippets
The implementation provides realistic pressure drops over any component, whilst being automatically adjusted to any design situation.
Info box displayed when toggling auto-connect (Ctrl+Shift+A)
An info box will now show if the auto-connect toggle is activated or deactivated when using Ctrl+Shift+A
Implemented minor bug fixes and technical improvements
Messages overview: Maintain Base Circuit selection when using navigation functionalities
Improved visuals of overrideable output parameters when in a group selection
Changes Jan 22, 2025
Introducing Pressure Drop in Design
All Kv value input parameters (end units, production units, …) can now be expressed as a pressure drop in design
The submitted pressure will use design condition properties to auto-scale the Kv value.
Kv(s) values (Metric) can now be expressed as Cv(s) values (Imperial)
New unit introduced in the unit list of model settings
Upgraded expansion vessel Base Circuit with extensive documentation, see Expansion Vessel
Improved parameter guidance
Extensive documentation to guide user to proper expansion vessel sizing
Improved the expansion vessel sizing method to facilitate more design situations
Updated the parameter list layout for better readability.
Wider parameter list ribbon bar
Better visibility of lengthy parameter names and lengthy parameter values
Improved the messages overview layout and navigation tools, see message overview
Introduced arrows to navigate through identical error occurences
Click on the error/warning/info icon in the messages overview to search the wiki
Improved operating range of chillers’ default performance tables
Minor UI changes:
Visuals of node error improved.
Improved the inspiration library buttons to state the functionality better
Introduced a tag at shared models to highlight that the model is uneditable.
Changes Jan 8, 2025
Introducing the message overview, see message overview
The message overview provides a concise overview of all error, warning and info messages in the model
The message overview can be opened with
in the top ribbon bar
In the message overview, you can easily navigate through
different occurences of the same error/warning
By clicking
or more info, you will automatically be directed to the corresponding documentation page.
Introduced orthogonal movement (Shift+Drag) on the Hysopt canvas
Constrain your drag movement to purely horizontal or vertical movement using this new functionality
Allows you to easily build and maintain structured Hysopt models.
Added user guidance and refresh option to floor plan upload page, see Floor plan manager
User guidance helps users applying the new zoom and pan view functionalities
Reload button
introduced to refit the floor plan to the available space
New hotkey: Quick select BC from library (Ctrl+Shift+Click).
New hotkey: Free rotate on floor plans (Ctrl + Shift + mouse move).
Changes Dec 11, 2024
Updates in the Hysopt model manager
You can now create Hysopt models outside a project for improved file structuring (if your license allows)
You can now delete projects and non-empty folders (if your license allows)
Pipe diameter dropdown improved for better usability
You can now adapt the pipe diameter directly without having to lock upfront
Pareto graph visuals enhanced for multi-screen support
Glycol mixture calculation bug at production units resolved
Several production units encountered (small) energy flow inconsistencies when working with non-water medium
Those issues are now resolved, and might have a small impact on existing model’s simulation results.
Changes Nov 26, 2024
Floor plan manager: Introduced zoom and pan for improved scaling, see Floor Plan Manager
You can now zoom on a floor plan in the floor plan manager by scrolling the mouse wheel when hovering over the floor plan
You can now pan over the floor plan in the floor plan manager, using either the right mouse button or the middle mouse button, depending on your user preference settings.
These enhancements make scaling of floor plans more precise and efficient.
New BC: 2-pipe storage tank now available in the cooling library
New BC: 3-pipe storage tank now available in the cooling library
Bug fix: User preferences now accessible on all screen sizes.
Changes Nov 12, 2024
Grid layer added to Hysopt canvas (Toggle with Alt+G), see Grid Layer
Detailed grid layer added to Hysopt canvas (toggle with Alt+Shift+G), see Detailed Grid Layer
Updated cooling tank visuals to clarify connection heights.
Cooling tanks using water as storage medium typically supply at the bottom of the tank and drain from the top.
The new visuals clearly display the standard situation to users
Fixed environment temperature display in pipe insulation input
The latest input is now correctly shown to the user when re-opening the pipe insulation parameter window.
New snippets added to the cooling library, see Snippets
Heat exchanger for cooling: Secondary temperature control
Changes Oct 29, 2024
Advanced tag added to signify less-crucial parameters, see Advanced Parameters
Typically for parameters that are more complex or already have suitable default values.
Ideal during project stages where detailed information is still unavailable.
Toggle for advanced parameters 
Provides a "focused view" by displaying only the most relevant parameters.
Visual differentiation for "default" values for better change tracking, see Change Tracking
Added option to toggle the visual changes for default values in user preferences.
Configurable list of units for new models added in user preferences, see User preferences - Unit list
Simulation bug with Central Heating on ILS blocks fixed
Changes Oct 15, 2024
Two new base circuits! Learn more about them at Thermal storage heating | Two pipe and three pipe storage tanks
2-pipe storage tank
3-pipe storage tank with one top and two bottom connections
New aggregation method based on CIBSE CP1 (2020) is now available under model settings. More info can be found here.
New snippets for cooling are added to the library for faster modeling.
Improved UI: Input parameters (white) are now visually distinct from output parameters (grey) for better clarity.
Input parameters now feature a white background, indicating they are editable by the user.
Output parameters now feature a grey background, signifying they are the result of a calculation.
Lockable parameters now behave more intuitively
Whenever the parameter is not locked, it is shown as an output parameter with a grey background
Whenever the parameter is locked, it is shown as an input parameter with a white background
Automatic locking introduced whenever user submits data for improved user experience.
You can find more info on the new parameter visualisations here.
Changes Sep 24, 2024
Sensitivity analysis is now possible on the Temperature constant
Two new manufacturer specific HIUs are available:
Baxi AquaHeat HI
Baxi AquaHeat HI/HWI
A new Activation Signal Generator base circuit (BC) is now available
Similar to the Setpoint Generator, but simpler for general activation signal needs
Misc. small improvements
Changes Sep 10, 2024
PNG files are now supported for floor plans. Previously, only PDF files were supported, but now you can also use a PNG file to create a floor plan.
Design Heat Flow and Regime parameters of various Thermal Store BCs have been updated to better indicate which can be set automatically and which need to be provided as input.
It is now possible to give a color to nodes in a model.
Changes Aug 27, 2024
Snippets with pre-configured controls are now available in the BC library for quick and easy model construction using the
icon. More information at How to model your system | Usage of pre built Snippets from the BC library .
The Snippets library will be extended over the coming weeks. Send your snippet requests to support@hysopt.com.
Changes Aug 13, 2024
Auto-scaling of the KVS-value of on/off valves is now set by default.
Improved information in the dynamic labels of various heat pump base circuits
Quick Drop On Canvas with Hotkey “Ctrl+D”. You can now easily place inserted templates or pasted clipboard content onto the canvas using the new hotkey "Ctrl+D". Simply insert your template or paste your clipboard content, and press "Ctrl+D" to instantly position it on your canvas.
Changes Jul 30, 2024
Auto-scaling of the thermal capacitance of production units is now set by default.
The programmable controller visuals have been upgraded. Users can now enter a custom display name to indicate the controller's application.
Changes Jul 16, 2024
Control nodes now clearly specify units wherever applicable.
Added a generic unit conversion base circuit (BC) to the control library, enabling convenient unit conversions over control lines. More info & how to use it at https://hysopt.atlassian.net/wiki/x/DICU2Q
Introduced a new temperature constant BC for defining constant temperature setpoints in Celsius (°C), Fahrenheit (°F), and Kelvin (K). More info & how to use it at https://hysopt.atlassian.net/wiki/x/A4CV2Q
A new base circuit “Dynamic electric boiler” is now available under the production units in the Hysopt library. More info & how to use it at Boilers | 5. Dynamic electric boiler
You can now give custom names to the input and output connectors of the programmable controllers via the “Visuals tab”.
You can also see these custom names when hovering over a connector on the canvas.
And you can also see these custom names in the series names of the graphs.
Changes Jul 2, 2024
Simulation parameters can be made visible by default through User Preferences
New inspiration library templates:
Gas boiler and heat pump control, including cascades (up to 5 identical units).
Chiller and heat pump control for cooling systems, including cascades (up to 5 identical units).
Pump control for heating systems (constant and variable speed).
Low-loss headers, heat exchangers, and thermal store controls.
Serial and shunt configurations for combining gas boilers and heat pumps in heating systems.
Changes Jun 18, 2024
Electrical power time series are now available in the graphs of electric immersion heaters
We have introduced the option to add multiple non-operational periods for setpoint profile.
Control lines can be colored using the newly introduced “Visuals“ tab
Changes Jun 4, 2024
Reversible Heat Pump dynamic label has been extended
COP and EER have been added
Temperature regime for the design conditions have been added
Polyvalent Four Pipe Heat Pump dynamic label has been added
Design conditions at design regimes
Pressure drops over the coils
Some commonly used functions were added to the code syntax of the programmable controller (abs, floor, ceil, sgn, tan), more info on Programmable controller ((extra) large) | Controller syntax
Changes May 21, 2024
You can now filter identical Base Circuits (BCs) from a group selection using the button
in the left ribbon bar.
Added a search bar to the inspiration library
, allowing you to filter using any text criteria.
Introduced support for links within the same canvas (hotkey: L).
It is now possible to enlarge/shrink control elements based on shortcuts "Ctrl Alt +" and "Ctrl Alt -"
Text objects now have a new parameter Alignment to set the horizontal text alignment.
The layout of the Pump Installation Report has been improved
Some minor bug fixes and technical improvements
Changes May 6, 2024
Some minor bugfixes and technical improvements
Changes Apr 23, 2024
Thermal capacitance auto-scaling is now available for all production units.
Some minor bug fixes and technical improvements.
Changes Apr 9, 2024
Some minor bugfixes and technical improvements
Changes Mar 26, 2024
The capacitance of all the heat pump BCs and KVS values of two-way and three-way valves can now be calculated using automated scaling by Hysopt. This feature comes as an addition over the existing method of entering the values manually or using calculator.
The Hysopt Platform now features improved support for named user licenses.
Some licenses, like Hysopt BIM Syncer, require specific assignment to users. This has been made easier and more consistent.
Such licenses can now be assigned to users and will then only be applicable to those users.
If no licenses are assigned, only non named licenses will get applied, as used to be the case
If licenses are assigned, they take precedence over automatically applied licenses, so then all required licenses should be assigned.
If multiple licenses are assigned (max 1 of each type), the user will receive the combination of features from all assigned licenses
Steps have been taken to ensure that existing license behavior is respected
Changes Feb 27, 2024
A new cost component “Carbon emissions tax” is available for the Pareto Analysis
The Admin Portal is undergoing changes to improve support for user bound licenses, like the BIM Syncer.
As such the User edit screens are extended with a License Assignments section.
License Assignments ExampleThis will enable assignment of licenses to individual users, potentially differentiating which features are available to which users.
This is a preparation step. There is no enforcement YET of the selections made here. This will come in an upcoming release.
Hence, no changes are required and license assignment will be handled automatically
Expect the BIM Syncer license assignment to be integrated into this screen in an upcoming release.
New "Polyvalent four-pipe heat pump" base circuit has been added to both the heating and cooling libraries. The polyvalent four-pipe heat pump is a heat-pump based production unit that can deliver simultaneous heating and cooling, independent heating and independent cooling all in one system.
For more info, see Polyvalent four-pipe heat pump
Changes Feb 13, 2024
More than 1200 new weather profiles for North America (USA and Canada)
The model being copied is now visible in the paste box when using the copy-paste functionality. The paste box changes to the grey paste box for bigger models to ensure better performance
A new feature of 'Job list view' is now available, it is possible to get an overview of different activities such as simulations, sensitivity analyses that were processed in the past.
This gives an overview of information such as
The activity type, activity name and duration of activity.
The model name for the activity.
The launched date-time of the activity.
The user who launched this activity.
The current activity status.
Filtering of activities can also be done in this view, the filtering can be done on the basis of
Activity type
Current status of the activity
Activities started between a particular time period
Activities launched by a particular user
Changes Jan 30, 2024
It is now possible to select the whole control path for a selected control line with the shortcut “Alt + h”. The user first needs to select a control line and then press the shortcut.
The color of selected control line is also modified to make it more visible against the white background, e.g., the control path connected to tap flow is selected after selecting a control line in this path
Changes Jan 16, 2024
New "Reversible heat pump" base circuit has been added to both the heating and cooling libraries. This new heat pump uses a reversing valve to switch between heating and cooling operation.
For more info, see Reversible heat pump
Changes Jan 2, 2024
It is now possible to give variants a custom name when doing a sensitivity analysis.
This name is also used in Pareto and for the generated model.
Changes Dec 18, 2023
Labels and dynamic labels can be rotated on a canvas (with shortcut 'R').
Changes Dec 5, 2023
Thermal storage anti-cycling volume determination will now be applied even if primary design heat flow and/or regime are locked.
Active mixing bypass valve can now be calculated correctly in situations where the primary pressure drop is zero.
Changes Nov 21, 2023
Heat Pump Chillers will now report design power in Energy Report
Improvements regarding authentication expiration
No more premature termination of authentication session
Possibility to recover from expired an authentication session
It is now possible to assign manufacturer specific HIU’s and pump groups to the electricity meter boxes, for more info, see Meter boxes
Changes Nov 7, 2023
The button to activate the Simulation mode has been moved from its original location to the top menubar of the Designer.
A canvas link can be renamed using the same tool to create one.
An HIU with embedded tap profile, for faster modelling, is added to the library.
Changes Oct 24, 2023
What’s New introduction
When new features are introduced a small message will show on first use, highlighting the new features
Sensitivity Analysis and Partial Load functions have moved
New navigation to the Sensitivity variant input is available in the top menubar of the Designer.
New unit selections in Model Settings
Monetary Amount related units are introduced
Usage of these units will be gradually introduced in upcoming releases
Some minor bugfixes and technical improvements
Changes Oct 10, 2023
New base circuit available that measures automatically all electrical consumption and production within the system
See Meter boxes | Auto assignable meter boxes for more infoAbsolute or relative input of the supply temperature of a heat exchanger for cooling
See Heat exchangers (HX) for more info
Changes Sep 27, 2023
Fix for issues with dynamic labels
Insert of models with dynamic labels (on some base circuits) was broken
Adding dynamic labels (on some base circuits) on floorplans was broken
Fix for issue with zone assignment of complex BCs
Changes Sep 26, 2023
Some models created between Sep 12, 2023 and Sep 26, 2023 , might have a deprecated diversity standard (based on DIN1988-300 v1) defined by default.
If that's the case for your model, the diversity standard will be automatically upgraded to the newer version (based on DIN1988-300 v2) when you open it again. This might influence (improve) your diversity calculations a bit.Simulation results are no longer lost on any save. They are retained until a change is made that could potentially influence the results.
E.g. Adding labels, moving BCs, ... should no longer lead to loss of simulation results
E.g. Changing a parameter, pipe length, model settings... will still lead to loss of simulation results on save as they constitute changes that will affect simulation results.
Introduction of multiple x-axes in graphs: we display multiple x-axes for the use cases where different series with different x-axis units get shown together.
Showing general simulation details in the sensitivity status page, i.e., start date, duration, weather profile are now visible in the sensitivity status page.
Some minor bugfixes and technical improvements
Changes Sep 12, 2023
Absolute or relative input of the supply temperature of a heat exchanger, more information: Heat exchangers (HX)
Non-operational temperature in setpoint profiles
in addition to day and night temperature, the temperature of non-operational period(s) can be configured
Some minor bugfixes and technical improvements
Changes Aug 29, 2023
New layers functionality
Toggle Canvas information
Text
Zones
Control
Floorplan
Note: The Canvas Selection button has received a new icon and the previous icon now serves to provide access to the Layers functionality
This layers functionality replaces the toggling effect of some of the library buttons
Some minor bugfixes and technical improvements
Changes Aug 15, 2023
New Zone Wall Temperature plot
New Thermal Storage Tank volume determination algorithms
Anti-cycling algorithm for the dimensioning of a storage tank in connection with a CHP (Combined Heat and Power) system, based on the Dutch ISSO publication 96 standard
Peak shaving algorithm for the dimensioning of a storage tank wih secondary HIU's, based on commonly used practices
More info: Thermal storage sizing algorithms
More BC's are now assignable to an electric meter box
production
header configurations
thermal storage
ambient exchange
change over
(ATES and HIU's will follow soon)
More info: Meter boxes
Some minor bugfixes and technical improvements
Changes Aug 1, 2023
Some minor bugfixes and technical improvements
Changes Jul 18, 2023
side navigation has been replaced by the new application bar
new start page for the designer with direct access to the model explorer and inspiration library
introduction of our new right sidebar
canvas selection has been moved to the right sidebar
current canvas name is visible (again) in the application bar
operation selection has been moved to the right sidebar
in addition to seconds, duration parameters can now also be entered in minutes and hours
heatpumps show calculated SCOP and SEER
heatpumps show start/stops per compressor stage if applicable
new Basecircuit "DesignValuesExtractor" to inject design values into your control logic
Some minor bugfixes and technical improvements
Changes Jul 4, 2023
Added modulation delay parameter for Heat Pumps
Some minor bugfixes and technical improvements
Changes Jun 28, 2023
The "Replace Base Circuit" operation (Ctrl+H) has been improved, connections are preserved in more situations
Some minor bugfixes and technical improvements
Changes Jun 23, 2023
Thermal Storage base circuits now show warnings when invalid temperature regimes are configured.
Heat pump base circuits can now be configured with VSD and fixed speed compressor configurations.
Integral series per month now take into account the actual days of each month in the simulation period, instead of always using 31 days.
(Integral series per month are only calculated if the simulation period starts on the first day of a month)Error and Warning counts now also shown after simulation
Some minor bugfixes and technical improvements
Changes Jun 6, 2023
Error and Warning counts now added to dialogs:
System Check
Compute Design Flows
Optimise Components dialogs
Some minor bugfixes
Changes May 23, 2023
Some minor bugfixes
Changes May 9, 2023
Some minor bugfixes and technical improvements
Changes Apr 25, 2023
New CIBSE CP1 based Managed Pressure Profile available
See Select pipes for more information
New Control BCs available for commonly used boolean operations (Updated documentation will follow)
And
Or
Not
Multi-color chart series highlighting
Hovering over a chart will highlight each featured series over the associated canvas element
Multiple series of the same element will lead to a multi-color highlight with each series color represented
This should allow for easier identification of the chart series on the canvas
Minor bug fixes
Changes Mar 28, 2023
Improved search functionality. Next to tags and labels, it is now possible to search within labels and component names. Either on the current canvas or across all canvasses.
Some minor bug fixes.
Changes Mar 14, 2023
Improve chart usability
Minor bug fixes
Changes Feb 28, 2023
Major UI release
Restyled Parameters
Collapsible Sidebar
Enhanced Charts for simulation results
Updated visuals
Extra export possibilities
Full screen view
Updated URLs
Minor sensitivity tweaks
Unit selection
Changes Jan 31, 2023
We are proud to announce that the Hysopt software has been validated by the ISSO institute: https://over.isso.nl/nieuws/validatie-hysopt
New default values for zone volume and window U-value parameters
Minor bug fixes and UI updates
Changes Jan 17, 2023
Minor bug fixes and UI updates