DA27 + DA28 GREEN STAR RECOGNITION
62
S
Sensor
Controlled Medium( Air temperature)
Controller
C Controlled Device
CD Chilled Water
Normally Supply Open
Cooling Coil
Chilled Water Return
Sensor S
INPUT
C
LOGIC
OUTPUT
Device
63
S Sensor
C
Cooling Coil
CD
Normally Open
Chilled Water Supply
Chilled Water Return
INPUT LOGIC
CD Controlled
DA27 + DA28 GREEN STAR RECOGNITION
THE AUSTRALIAN INSTITUTE OF REFRIGERATION, AIR CONDITIONING AND HEATING
••• 24
DA27 BUILDING COMMISSIONING BUILDING COMMISSIONING DA27
The commissioning process
Pre design
Design
Install
Test
Handover
Owning
The commissioning manager can assist the owner and building designers define the POR, the content of which is discussed in Section 5.
3.4.3. Assemble commissioning team
The next step is to put together the commissioning team. The role of the commissioning team is to oversee the entire commissioning process.
• Assign a commissioning manager
• Document owner’ s requirements
• Assemble commissioning team
• System design reviews
• Design review reports
• Commissioning ream review
• Construction documentation review
• Systems installation / site review
• Building documentation review
• Test reports
• Diagnostic monitoring
• Functional tests and TAB
• Final building documentation
• Training
• Operations review and building tuning
• Tuning and maintenance
• Persistance strategies
• Continuous commissioning
• Pre-design commissioning meeting
• Draft scope of work
• Outline commissioning plan
• Design issues and changes
• Commissioning specification
• Updated commissioining plan( Design)
• Documenting issues and changes
• Finalise test procedures
• Updated commissioning plan( Install)
• Integrated tests
• Building preformance tests and seasonal tests
• Updated commissioning plan( Test)
• Final commissioning report
• Lessons learned at meeting
• Recommissioning
• Retrocommissioning
• Replacement
Figure 3.1: The Commissioning Process
The commissioning team will:
• Provide a forum for inter trade communication.
• Provide a mechanism for the clear allocation of project responsibilities.
• Participate in commissioning reviews.
• Assist with non-conformance resolution.
• Approve the commissioning and tuning plans.
• Approve the commissioning report.
The commissioning manager chairs the commissioning team meetings and is ultimately responsible for assigning commissioning task responsibilities and signing off on required verification steps.
Stakeholders that should be represented on the commissioning team include:
• Owner’ s representative.
• Facility management staff.
• Maintenance manager.
• Occupant or tenant representative.
• Main contractor.
• Building services subcontractors.
• Specific equipment manufacturers.
• Building designers and architect.
• Controls contractor or supplier.
• Building services designers.
Not all of these stakeholders will be available at the beginning of the project. The make-up of the commissioning team will evolve over the course of the project as key stakeholders become involved in the process, and depending on the contractual structure of the project. It is essential however, that all key project participants are included at the earliest possible stage to ensure that the owner’ s expectations and individual project commissioning responsibilities are clearly allocated and understood. It is also essential that once these stakeholders are engaged in the project, the actions and responsibilities that have been delegated to them and the commissioning expectations of them are clearly communicated to them and understood and accepted by them.
Periodic meetings of the commissioning team are essential to a successful building commissioning process. More frequent team meetings are generally required during the later stages of construction, testing and handover as this is the phase of the project when most errors or conflicts can arise and when there is the least amount of time and resources available to resolve them.
3.4.4. Pre-design meeting
An important step in the process is to hold a pre-design meeting of the commissioning team. This is an opportunity for the commissioning manager and owner to introduce all stakeholders, explain the commissioning process, allocate all responsibilities( clarifying any overlaps), coordinate the commissioning activities, and clearly outline the expectations for all parties.
The owner should fully empower the commissioning manager at this time to ensure that all stakeholders in the project are fully aware of the owner’ s expectations with regard to building commissioning. The pre-design meeting is also an opportunity for commissioning team members to share lessons learned from previous commissioning projects.
DA27 BUILDING COMMISSIONING BUILDING COMMISSIONING DA27
The commissioning process
••• 24
Pre design
Design
Install
Test
Handover
Owning
3.4.5. Roles and responsibilities
Not all project stakeholders( e. g. specialist contractors and subcontractors) will be engaged in the project at this early stage however, their roles and responsibilities still need to be allocated and defined at this point. Once these stakeholders are engaged in the project and join the commissioning team they should be asked to sign off or confirm the roles and responsibilities that have been allocated to them. These roles and responsibilities should be detailed as part of the conditions of contract, not after the awarding of the contract or subcontract works.
• Assign a commissioning manager
• Document owner’ s requirements
• Assemble commissioning team
• System design reviews
• Design review reports
3.4.6. Define scope of work
One of the pre-design deliverables of the commissioning team is a well-defined and agreed scope of work for the project so that the design phase can be carried out. The scope of work will form part of the commissioning plan.
• Commissioning ream review
3.4.7. Draft commissioning plan( outline)
• Construction documentation review
• Systems installation / site review
Once the scope of work has been defined, an outline of the commissioning plan will be developed by the commissioning manager. The commissioning plan is a document that evolves with the project and is reviewed and updated at several stages during the project. See figure 3.2. Developing an outline of the commissioning plan at the pre-design stage helps the commissioning team to focus on the commissioning requirements of the design stage of the project.
The commissioning plan serves as a focus point for the commissioning team throughout the project. At pre-design stage it will specify the design related commissioning tasks and schedules. At design stage it will specify the construction related commissioning tasks and schedules. At construction stage it will specify the handover related commissioning tasks and schedules. At handover stage it will specify the building tuning related commissioning tasks.
• Building documentation review
• Test reports
• Diagnostic monitoring
• Functional tests and TAB
• Final building documentation
• Training
• Operations review and building tuning
• Tuning and maintenance
Final Test commissioning Design plan
Install
Outline
• Persistance strategies
• Continuous commissioning
The commissioning manager can assist the owner and building designers define the POR, the content of which is discussed in Section 5.
3.4.3. Assemble commissioning team
APPLICATION MANUAL
Figure 3.2: Commissioning Plan updated after each phase
The next step is to put together the commissioning team. The role of the commissioning team is to oversee the entire commissioning process.
• Pre-design commissioning meeting
DA27
• Draft scope of work
• Outline commissioning plan
• Design issues and changes
• Commissioning specification
• Updated commissioining plan( Design)
• Documenting issues and changes
• Finalise test procedures
• Updated commissioning plan( Install)
BUILDING COMMISSIONING
• Integrated tests
• Building preformance tests and seasonal tests
• Updated commissioning plan( Test)
• Final commissioning report
• Lessons learned at meeting
• Recommissioning
• Retrocommissioning
• Replacement
The commissioning team will:
• Provide a forum for inter trade communication.
• Provide a mechanism for the clear allocation of project responsibilities.
• Participate in commissioning reviews.
• Assist with non-conformance resolution.
• Approve the commissioning and tuning plans.
• Approve the commissioning report.
••• 25
Figure 3.1: The Commissioning Process
The commissioning manager chairs the commissioning team meetings and is ultimately responsible for assigning commissioning task responsibilities and signing off on required verification steps.
Stakeholders that should be represented on the commissioning team include:
• Owner’ s representative.
• Facility management staff.
• Maintenance manager.
• Occupant or tenant representative.
• Main contractor.
• Building services subcontractors.
• Specific equipment manufacturers.
• Building designers and architect.
• Controls contractor or supplier.
• Building services designers.
Not all of these stakeholders will be available at the beginning of the project. The make-up of the commissioning team will evolve over the course of the project as key stakeholders become involved in the process, and depending on the contractual structure of the project. It is essential however, that all key project participants are included at the earliest possible stage to ensure that the owner’ s expectations and individual project commissioning responsibilities are clearly allocated and understood. It is also essential that once these stakeholders are engaged in the project, the actions and responsibilities that have been delegated to them and the commissioning expectations of them are clearly communicated to them and understood and accepted by them.
Periodic meetings of the commissioning team are essential to a successful building commissioning process. More frequent team meetings are generally required during the later stages of construction, testing and handover as this is the phase of the project when most errors or conflicts can arise and when there is the least amount of time and resources available to resolve them.
3.4.4. Pre-design meeting
An important step in the process is to hold a pre-design meeting of the commissioning team. This is an opportunity for the commissioning manager and owner to introduce all stakeholders, explain the commissioning process, allocate all responsibilities( clarifying any overlaps), coordinate the commissioning activities, and clearly outline the expectations for all parties.
The owner should fully empower the commissioning manager at this time to ensure that all stakeholders in the project are fully aware of the owner’ s expectations with regard to building commissioning. The pre-design meeting is also an opportunity for commissioning team members to share lessons learned from previous commissioning projects.
3.4.5. Roles and responsibilities
Not all project stakeholders( e. g. specialist contractors and subcontractors) will be engaged in the project at this early stage however, their roles and responsibilities still need to be allocated and defined at this point. Once these stakeholders are engaged in the project and join the commissioning team they should be asked to sign off or confirm the roles and responsibilities that have been allocated to them. These roles and responsibilities should be detailed as part of the conditions of contract, not after the awarding of the contract or subcontract works.
3.4.6. Define scope of work
One of the pre-design deliverables of the commissioning team is a well-defined and agreed scope of work for the project so that the design phase can be carried out. The scope of work will form part of the commissioning plan.
3.4.7. Draft commissioning plan( outline)
Once the scope of work has been defined, an outline of the commissioning plan will be developed by the commissioning manager. The commissioning plan is a document that evolves with the project and is reviewed and updated at several stages during the project. See figure 3.2. Developing an outline of the commissioning plan at the pre-design stage helps the commissioning team to focus on the commissioning requirements of the design stage of the project.
The commissioning plan serves as a focus point for the commissioning team throughout the project. At pre-design stage it will specify the design related commissioning tasks and schedules. At design stage it will specify the construction related commissioning tasks and schedules. At construction stage it will specify the handover related commissioning tasks and schedules. At handover stage it will specify the building tuning related commissioning tasks.
Outline
Final Test commissioning Design plan
Install
Figure 3.2: Commissioning Plan updated after each phase
••• 25
THE AUSTRALIAN INSTITUTE OF REFRIGERATION, AIR CONDITIONING AND HEATING
•••
DA28 BUILDING MANAGEMENT & CONTROL SYSTEMS BUILDING MANAGEMENT & CONTROL SYSTEMS DA28
as-installed drawings reflect what has been corrected to gain a more efficient and manageable building system.
10.9. System management
10.9.1. System access
It is important to decide who has access to the BMCS controls. The following stakeholders generally need some form of access to system settings:
• System operators – Day to day operational tasks.
• Maintenance providers – System interrogation, monitoring.
• Building tuning team – Fine tuning control loops
• Specialist or vendor representatives – Updates and fixes.
The level of access and authority to make changes must be clearly identified and defined for each individual.
10.9.2. Change management
It is important for BMCS, or any DDC control system, that a formal change management system is put in place. Unauthorised changes and quick fixes are common reasons why system controls operate inefficiently. Only specified people should be given access to the BMCS and the responsibility or authority for changing controls settings, control routines, and controls logic should be nominated.
• Control settings – Changing set points and targets, room temperature settings, set back temperatures.
• Control routines – Changing parameters associated with systems control philosophy.
• Control logic – Changing code in the controller programming.
When making changes to system operating controls or settings, it is important to consider all of the consequences of the change made. The system should be set up to record and show who was logged onto the system, what changes if any were made, and the underlying reasons why the changes were made.
10.9.3. Documenting changes
Ideally a building tuning plan should be in place to introduce a standardised process for managing changes to the control system. All changes that are authorised should be fully documented and the building documentation and BMCS information updated as appropriate.
10.9.4. Verifying systems
Even with strong policies in place, it may be difficult to guarantee that unauthorised changes have not been made and it is worthwhile to periodically verify and sign off that rogue control strategies or changes have not been implemented.
10.10. Post occupancy evaluation
Also termed building performance evaluation, this activity focuses on determining how well the building is meeting its defined operating requirements and assesses the level of satisfaction or dissatisfaction of building occupants and users.
Post occupancy evaluation usually focuses on energy usage figures and occupant evaluation surveys, although criteria will vary from facility to facility.
Any evaluation process needs to include a formal evaluation of the building performance information and survey results, generally by a tuning or building performance team.
10.11. Performance review
The specific requirements of the building or individual spaces may change over time and there should be some form of review to adjust systems to the specific requirements. Where no particular changes have occurred, systems will still need to be finetuned. Minor changes may lead to a recommissioning program whereas major changes in the operating requirements may lead to system or building retrocommissioning.
• Fine tuning – Uses tests and procedures as detailed in the building tuning manual.
• Recommissioning – Uses the same tests and procedures as utilised for the original commissioning program.
• Retrocommissioning – Uses new tests and procedures developed specifically for the new or modified system.
10.12. Recommissioning
Recommissioning begins with a review of the project operating requirements( POR) to determine what, if any, changes have occurred. The POR needs to be updated or confirmed prior to any recommissioning activities commencing.
If changes have occurred, systems are reviewed to establish if corresponding changes to equipment, controls or operation procedures are required.
Systems are then fully surveyed and a list of findings or issues compiled.
System trend logs or functional performance tests may be used to determine if the systems meet the performance defined in the reviewed and updated project operating requirements( POR).
10.13. Upgrades
Replacement strategy – scheduling the replacement of inefficient equipment with modern high efficiency alternatives( always review the load requirements for changes).
Appendix A
This Appendix provides a broad overview of control system fundamentals and explains some of the common terms used when discussing control systems. For more detailed technical information on any of this material refer to CIBSE Guide H Building Control Systems or similar publications.
Manual control requires direct control of a system by human intervention. Automatic controls function without direct human intervention once set in motion. Automatic controls act to maintain a predetermined set point in response to changing conditions.
At its most fundamental, a control system comprises a sensor, a controller, a controlled device, a process, and a feedback to the system. Closed loop systems have a direct feedback via the sensor; open loop systems have no direct feedback. The set point is the desired or pre-set value of the variable for the feedback loop to compare against, e. g. the temperature of a space or the pressure of a fluid.
••• 62
Figure A1: Basic control loop
A sensor detects and measures a variable and sends this information to the controller. Sensors typically measure temperature, pressure, humidity, velocity, flow, illuminance, movement, substance concentration, electrical resistance, or electronic voltage. Sensor output becomes controller input.
The controller receives the information from the sensor and uses a pre set logic or control algorithm to compute an output signal which it sends to the controlled device. Controller output becomes controlled device input.
The controlled device receives the information from the controller and acts on it to make the required change to the system. Examples of controlled devices are modulating
DA28 BUILDING MANAGEMENT & CONTROL SYSTEMS BUILDING MANAGEMENT & CONTROL SYSTEMS DA28
as-installed drawings reflect what has been corrected to gain a more efficient and manageable building system.
10.9. System management
10.9.1. System access
It is important to decide who has access to the BMCS controls. The following stakeholders generally need some form of access to system settings:
• System operators – Day to day operational tasks.
• Maintenance providers – System interrogation, monitoring.
• Building tuning team – Fine tuning control loops
• Specialist or vendor representatives – Updates and fixes.
The level of access and authority to make changes must be clearly identified and defined for each individual.
Controls fundamentals
10.9.2. Change management
It is important for BMCS, or any DDC control system, that a formal change management system is put in place. Unauthorised changes and quick fixes are common reasons why system controls operate inefficiently. Only specified people should be given access to the BMCS and the responsibility or authority for changing controls settings, control routines, and controls logic should be nominated.
• Control settings – Changing set points and targets, room temperature settings, set back temperatures.
• Control routines – Changing parameters associated with systems control philosophy.
• Control logic – Changing code in the controller programming.
When making changes to system operating controls or settings, it is important to consider all of the consequences of the change made. The system should be set up to record and show who was logged onto the system, what changes if any were made, and the underlying reasons why the changes were made.
10.9.3. Documenting changes
Ideally a building tuning plan should be in place to introduce a standardised process for managing changes to the control system. All changes that are authorised should be fully documented and the building documentation and BMCS information updated as appropriate.
10.9.4. Verifying systems
Even with strong policies in place, it may be difficult to guarantee that unauthorised changes have not been made and it is worthwhile to periodically verify and sign off that rogue control strategies or changes have not been implemented. valves and dampers, lighting dimmers, variable speed motors( that drive fans, pumps and compressors), electrical or electronic switches and capacitors.
A sensor, controller and controlled device can all live in the same box or they can be in three separate places. They need to be connected to communicate, connections can be wired or wireless. Sensor output becomes controller input and controller output becomes device input. A thermostat is both a sensor and a controller; a thermostatic valve is a sensor, a controller and a controlled device. The load or process typically includes building ventilation, cooling, heating, lighting, transport, and security access.
Into DDC Out of DDC
Controller
10.10. Post occupancy evaluation
Also termed building performance evaluation, this activity focuses on determining how well the building is meeting its defined operating requirements and assesses the level of satisfaction or dissatisfaction of building occupants and users.
Post occupancy evaluation usually focuses on energy usage figures and occupant evaluation surveys, although criteria will vary from facility to facility.
Any evaluation process needs to include a formal evaluation of the building performance information and survey results, generally by a tuning or building performance team.
DA28
10.11. Performance review
The specific requirements of the building or individual spaces may change over time and there should be some form of review to adjust systems to the specific requirements. Where no particular changes have occurred, systems will still need to be finetuned. Minor changes may lead to a recommissioning program whereas major changes in the operating requirements may lead to system or building retrocommissioning.
• Fine tuning – Uses tests and procedures as detailed in the building tuning manual.
• Recommissioning – Uses the same tests and procedures as utilised for the original commissioning program.
• Retrocommissioning – Uses new tests and procedures developed specifically for the new or modified system.
BUILDING MANAGEMENT AND CONTROL SYSTEMS( BMCS)
10.12. Recommissioning
Recommissioning begins with a review of the project operating requirements( POR) to determine what, if any, changes have occurred. The POR needs to be updated or confirmed prior to any recommissioning activities commencing.
If changes have occurred, systems are reviewed to establish if corresponding changes to equipment, controls or operation procedures are required.
Systems are then fully surveyed and a list of findings or issues compiled.
System trend logs or functional performance tests may be used to determine if the systems meet the performance defined in the reviewed and updated project operating requirements( POR).
CD Controlled
Figure A2: DDC inputs and outputs
A direct acting control action means the output increases with increases in the measured variable.
A reverse acting control action means the output decreases as the measured variable increases.
Examples of controllers are thermostats, programmable timers, microprocessor controls, direct digital control systems( DDC), and building management and control systems( BMCS). How the controller functions, its internal logic, determines the relationship between the controllers input and output. This is called the control response.
Typical control responses employed in building HVAC are:
• Two position – This is essentially an on / off control based on the specified set point and differential. The output is off when the set point is reached, and on when the difference between the set point and the measured variable( the differential) reaches the specified value.
10.13. Upgrades
Replacement strategy – scheduling the replacement of inefficient equipment with modern high efficiency alternatives( always review the load requirements for changes).
APPLICATION MANUAL
•••
Appendix A
This Appendix provides a broad overview of control system fundamentals and explains some of the common terms used when discussing control systems. For more detailed technical information on any of this material refer to CIBSE Guide H Building Control Systems or similar publications.
Manual control requires direct control of a system by human intervention. Automatic controls function without direct human intervention once set in motion. Automatic controls act to maintain a predetermined set point in response to changing conditions.
At its most fundamental, a control system comprises a sensor, a controller, a controlled device, a process, and a feedback to the system. Closed loop systems have a direct feedback via the sensor; open loop systems have no direct feedback. The set point is the desired or pre-set value of the variable for the feedback loop to compare against, e. g. the temperature of a space or the pressure of a fluid.
Controlled Medium( Air temperature)
Controller
Figure A1: Basic control loop
A sensor detects and measures a variable and sends this information to the controller. Sensors typically measure temperature, pressure, humidity, velocity, flow, illuminance, movement, substance concentration, electrical resistance, or electronic voltage. Sensor output becomes controller input.
The controller receives the information from the sensor and uses a pre set logic or control algorithm to compute an output signal which it sends to the controlled device. Controller output becomes controlled device input.
The controlled device receives the information from the controller and acts on it to make the required change to the system. Examples of controlled devices are modulating
Controls fundamentals
Controlled Device valves and dampers, lighting dimmers, variable speed motors( that drive fans, pumps and compressors), electrical or electronic switches and capacitors.
A sensor, controller and controlled device can all live in the same box or they can be in three separate places. They need to be connected to communicate, connections can be wired or wireless. Sensor output becomes controller input and controller output becomes device input. A thermostat is both a sensor and a controller; a thermostatic valve is a sensor, a controller and a controlled device. The load or process typically includes building ventilation, cooling, heating, lighting, transport, and security access.
Sensor S
Into DDC Out of DDC
C Controller
Device
OUTPUT Figure A2: DDC inputs and outputs
A direct acting control action means the output increases with increases in the measured variable.
A reverse acting control action means the output decreases as the measured variable increases.
Examples of controllers are thermostats, programmable timers, microprocessor controls, direct digital control systems( DDC), and building management and control systems( BMCS). How the controller functions, its internal logic, determines the relationship between the controllers input and output. This is called the control response.
Typical control responses employed in building HVAC are:
• Two position – This is essentially an on / off control based on the specified set point and differential. The output is off when the set point is reached, and on when the difference between the set point and the measured variable( the differential) reaches the specified value.
••• 63
DA27 Building Commissioning and DA28 Building Management and Control Systems have been recognised in a GBCA technical clarification. This means that Australian industry can work with processes and documents that they understand. References are to Australian law, Australian regulations, Australian Standards and Australian practices – and all in a language and vernacular that Australian industry can understand.
Purchase online at www. airah. org. au