Main Page
Introduction
This is a new wiki site, started in May 2022, devoted to open source controls in the HVAC industry with a view to reducing carbon emissions.
Anyone can make use of the material on this site.
Collaboration on producing this site is open to anyone with related technical material to contribute in relation to the projects listed. Please contact the admin with your intent, and please do not edit other people's work. Any additions that do not specifically contribute technical material related to lowering carbon may be removed without notice, as will any commercially sensitive material or advertising.
If you have a new project and you wish to collaborate, please contact us.
Quick Links
Purpose of this Wiki
- To provide instruction manuals for project related open source hardware and software
- To establish open standards for data labelling and communication (HVAC-MQTT dictionary)
- To establish open standards for equipment control at a software level
- To record processes, procedures and software functions
- For the recording and dissemination of data from field trials related to open technologies and zero-carbon
- To store any media and data that is useful for open-source control
- To provide links to web sites including related GitHub projects
- To demonstrate and experiment with how a wiki can be used (alongside real-time data) to create a feedback loop (between designers and users) to improve outcomes
- Saving carbon through collaboration
Current Collaborators
- Thermal Integration Ltd. (Heatweb)
- Swansea University
- Specflue
- Putney Plaza Management Group & Residents' Committee
Creating new pages on this Wiki
When creating pages, please do so by first creating a link in the appropriate sections below, and then following the link to create the page. This ensures all pages are linked.
You create a link when editing by typing two consecutive opening square brackets... [[
Projects
The following projects and field trials are the focus of this wiki. Hardware and software is been improved to ensure outcomes meet expectations, with the wiki used as a knowledge base for collaboration.
| Project Title | Description | Links |
|---|---|---|
| Specflue Training Centre Refit | Specflue run the UK's largest renewables training centre with lots of low carbon heat sources to be controlled. The project involves the upgrade of existing controls to use the new open controls standards. |
|
| Swansea University, Solar Heat Energy Demonstrator (SHED) | The Solar Heat Energy Demonstrator in Margam is used to trial two large-scale solar heat storage demonstrators. It is a 1990’s industrial unit that has been retrofitted with solar technology, and as a result, has been running without gas since 2012. The SHED is also home to two other major projects: Transport for Wales’ Active Train Shelter and a test-rig to analyse five commercially available PV and solar thermal technologies.
The project involves the upgrading of the SHED to run on CO2 heat pumps alongside existing solar thermal, providing hot water and driving numerous workspaces with central heating provided by a range of methods, with a view to discovering and documenting best practices. |
|
| Putney Plaza | Putney Plaza is a residential development in South London using gas boilers, CHP and roof mounted air source heat pumps.
The project involves the upgrading of heat pump and chp controls to bring them back online. Residents and management will be provided with an online dashboard to keep track of performance and efficiencies. |
|
| Sandbox Demo | An sandbox project, purely for experimenting and demonstration of technologies. Use this project to test out wiki features and see examples of how data can be presented on pages. |
Primary Applications
Buffer & Thermal Store Controller
Every heating or hot water system that involves renewable energy requires storage, be it a hot water cylinder in a dwelling, or a buffer store in a heat network.
This application follows the current guidance, including CP1 Codes of Practice, and industry best practices, to deliver a buffer control solution.
Functions:
- Buffer and pipe temperature and pressure sensing
- Bivalent control with storage zoning
- Multiple store control with service mode
- Boiler (gas and biomass) and heat pump sequencing, rotation and modulation based on store depletion (as per CP1)
- Solar thermal control
- Overheat functions for biomass and solar systems
- Low storage override functions (shedding of non-critical loads)
- MQTT services, dashboards and remote monitoring
HIU Monitoring and Controls Refurbishment
This application makes use of open-source controls to add monitoring to existing HIU installations, and also to allow controls to be upgraded to comply to best practices and achieve lower return temperatures.
Fan Coil Monitoring and Control
With a significant number of fan coil units and convector heaters out there connected to heat networks, it is important to get a grip on performance and to implement a better standard of controls.
This project application provides both monitoring and valve control to achieve lower return temperatures and manage outputs to better match loads.
This application extends to the monitoring and control of heat pumps and associated three port valves.
Heat Network Management
This application demonstrates how other applications can combine to form larger more complex networks and their control mechanisms.
This is a cloud or panel based installation of the open controls software, pulling together the data from devices to provide remote management and alarm routing.
Secondary Applications
IPFS Data Storage
A peer-to-peer data storage system aimed at providing persistent data storage and better identification of data.
Files and data stored on IPFS are given a hash identifier that directly relates to content, so any changes in content result in a change of file name. This allows us to store data in various forms, including directory structures, with no possibility of filename duplication.
IPFS is used in numerous applications, including the 'off-chain' storage of data for blockchains. As long as someone somewhere has the data 'pinned' then it remains accessible to all. IPFS was recently used to backup the entire Turkish Wikipedia follow government plans to take it down. The site now persists in a fashion that cannot be taken down. https://en.wikipedia.org/wiki/InterPlanetary_File_System#Other_notable_uses
An example of IPFS in action can be seen on the Heat Network Designer where it is used to save the complete design as well as outputs into a JSON file, so it can be shared via a short URL.
e.g. https://hw7.ddns.net/ui/hndesign?loadCID=QmegcRKHhunR6ZR4Vvo65NEMHzau8c9CNrR1GMi7YfZT3N
Hardware
The primary controls hardware used in this project is the Heatweb BEMS Hat for the Raspberry Pi (or BeagleBone).
This is a general purpose I/O board providing a full suite of inputs, outputs and communication buses for use in the HVAC industry. Combined with Node-RED the board offers a complete open-source controls solution for all common equipment.
The boards run from a 12v dc supply, generating 5v for the board, 24v for valves, and 36v for M-Bus, using on-board dc-dc converters backed up by a rechargeable battery for uninterrupted power supply. A coin cell is used to power a real-time clock.
The I/O includes:
- NTC or 0-10v temperature and pressure sensors
- Pulse flow sensors and meters
- Volt-free signals from relays
- Relay outputs
- PWM inputs and outputs for valves and pumps
- 0-10v outputs for pumps, valves and boilers
- RS485 for Modbus communications with pumps, boilers, HIUs and BMS systems
- M-Bus meter communications
WiFi, Ethernet and Bluetooth are provided by the Raspberry Pi board.
A number of the inputs are universal, and can be switched between NTC, 0-10v, or volt-free / pulse inputs (jumper selected). This ability to alter the hardware setup increases versatility significantly.
The addition of M-Bus allows us to connect to heat meters as standard, making the board a stand alone solution to open-sourcing meter data, and to use meter data within control logic.
The battery backup allows us to safely shut-down all valves and the controls when power is removed. This overcomes a common problem with HVAC systems, where valves typically remain open, destroying network performance.
Software
The following links relate to software used in projects on this wiki.
Please Help
We need help in this project with the following:
- We are looking to recruit a skilled software engineer, capable of developing in Node.js and Linux embedded systems.
- We need to recruit keen engineers who wish to become one of the next generation of open-source controls installers.
- We are looking for properties to participate in field trials, where we can upgrade radiator controls and monitor performance through next Winter.
- We would like to talk to local authorities with residential blocks that have a roof space for a heat pump and wish to perform trials, or have energy centres that they would like to gain transparency on with a view to future zero-carbon upgrades.
We also have some functions we would like to build into open libraries but currently lack the knowledge to achieve properly. Help would be appreciated:
- Bluetooth App that runs on IoS and Android, linking forms and web pages generated from Node-RED templates to App to enable user interfaces to be entirely driven from Node-RED. Working prototype version exists for Android using MIT App Inventor 2.