ECS II Commissioning

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Building commissioning (Cx)

A systematic quality assurance process that spans the entire design and construction process, helping ensure that the new building's performance meets owner expectations.

Adjust

To proportion flows of fluids (air & water) to specified design quantities. • Adjusting is the final setting of balancing devices such as dampers and valves, adjusting fan speeds and pump impeller sizes, in addition to automatic control devices such as thermostats and pressure controllers to achieve maximum specified system performance and efficiency during normal operation.

Test

To determine the quantitative performance of equipment • Testing is the use of specialized and calibrated instruments to measure temperatures, pressures, p , p , rotational speeds, electrical characteristics, velocities and air and water quantities for an evaluation of equipment and system performance.

Balance

To regulate the specified fluid flow rate at the terminal equipment • Balancing is the methodical regulation of system fluid flows (air or water) through the use of acceptable procedures to achieve the desired or specified airflow or water flow.

Occupancy and Operations

Upon turnover, the building is in the hands of the owner and operators. Although the project is considered complete, some commissioning tasks continue during the typical one‐year warranty period. The active involvement of the commissioning lead during the initial occupancy period is essential to the success of the commissioning process.

Commissioning

Verifies that the systems were appropriately selected & designed, correctly installed & programmed, are operating as intended, and the Owner has the resources & training to operate the systems

Average Payback of 10 Buildings

• 2.67 Years • Total cost savings of $60 million has been well documented

In a study of 60 new buildings

• 50 percent suffered controls problems • 40 percent suffered HVAC problems • 15 percent had missing equipment • 25 percent of the economizers and VFDs didn't function • In addition, 60 percent of all insurance claims were HVAC related • The No. 1 source of complaints was HVAC

HVAC Balancing

• Balancing will be applied to both Air side and Water side. • Balancing of air side is known as Air Balancing and water side is known as Water or Hydronic Balancing

Typical Problems Found

• Blocked valve handle • Gaps in ductwork • Broken damper arm • Faulty controls • Wrong controls sequence • Plugged filter • Photo sensor blocked by duct or wall • Photo sensor aimed at ceiling, not task plane • Missing sensor • Exhaust fan hardwired "on"

Commissioning Team Members

• Commissioning Lead (CxP) • Building Owner or Owner's Representative • Building Manager and Staff • Design Professionals • Contractors • Manufacturer's Representatives • Testing Specialists

Commissioning Benefits

• Construction cost savings • Improved coordination between design, construction, and occupancy • Fewer system deficiencies at building turnover • Energy savings • Improved indoor environmental quality

Commissioning Costs

• Difficult to estimate • No standard convention for determining which costs are included in the total cost of commissioning. • The commissioning lead's fee is the most obvious cost • The cost of correcting problems • When the dollar value of commissioning's benefits are taken into account, the cost of commissioning is often offset by more than 50%. • Ability to reduce a building's net lifecycle costs and its potential to reduce first costs

Preventive Maintenance

Saves energy, increases equipment life, and helps prevent unexpected equipment failure. Preventive maintenance can save building owners time and money by: • Maintaining efficient facility operations • Extending equipment life • Increasing energy savings • Preventing loss of equipment, time, productivity, and the resulting revenue

The Commissioning Process

1. Pre‐Design 2. Design 3. Construction 4. Occupancy and Operations

HVAC Commissioning Benefits

1. Reduction of change orders and additional claims 2. Fewer deficiencies at substantial completion 3. Fewer project delays ETC.

Commissioning Statistic

"...the owner has recovered the full cost of the commissioning process about 80% of the way through design..."

Goals of the Commissioning Process

1. Document the building's functional and performance requirements 2. Provide tools and documentation to improve the project team's deliverables 3. Verify and document that systems perform as specified in the Owner's Project Requirements (OPR) 4. Verify that the building owner and manager receive adequate and accurate system documentation and staff training 5. Bring a holistic perspective to the design and construction process that integrates and enhances its traditionally separate functions

Eight design considerations that facilitate good O&M

1. Ground‐floor access to the chiller room through a connected loading dock 2. One or more roll‐up doors of sufficient size to permit removal and replacement of chillers or other major equipment j q p without the need to disassemble equipment 3. Sufficient clearance on all sides of the chiller and other major equipment to perform all maintenance 4. Hoist or crane equipment over banks of chillers or other major equipment 5. Sufficient valves to permit the isolation of an individual chiller without having to shut down the entire system 6. Walkways around elevated equipment 7. Roof access with adequate openings via stairs, not ladders 8. Direct ceiling access to each terminal box

Continuous Commissioning SM

A continuous process of collecting and analyzing energy data via a existing metering equipment, and making the necessary operational changes to keep building systems operating at optimal performance levels in future years.

LEED Requirements

All buildings seeking LEED certification must implement a commissioning process that meets the LEED Rating System guidelines • All the rules are meant to avoid a conflict of interest between the Cx and the Owner's interest's. An independent third‐party provider is best option.

Recommissioning

Another type of commissioning that occurs when a building that has already been commissioned undergoes another commissioning process.

Pre-Design

Critical to the success of the project. They build a strong foundation for both commissioning and construction activities.

Construction

During construction, the commissioning lead monitors numerous aspects of the project to ensure that building systems and equipment are installed and tested according to the owner's requirements.

Design

In design, the project evolves from concept to plan, as architects and engineers develop drawings, draft construction documents and write specifications. Commissioning ensures that as the building becomes a reality, its systems and operations continue to reflect the owner's goals.

Building Staff Training

One of the essential components of an excellent O&M program is training. Unless operators and managers have the right knowledge and skills, it will be impossible for the building to perform optimally over time.

3 Steps of TAB

Test, Adjust and Balance, repeat until desired result is achieved

Retrocommissioning

The application of the same process to existing buildings

The Commissioning Team's Role

The commissioning team does not manage the design and construction of the project. Its purpose is to promote communication among team members, identify and resolve problems early in the process, and document the performance of the building.

What is commissioning?

The term commissioning comes from shipbuilding. A commissioned ship is one deemed ready for service. On a ship: "Will it float?" versus "Does the engine start?" In a building: "Does a fan work?" versus "Should it be on?"

Test & Balance

historically was the method used to verify that the HVAC systems were simply operational checks a limited number of systems towards the conclusion of the construction phase

Testing Adjusting Balancing (TAB)

the process of checking and adjusting all building environmental systems to produce the design objectives

Sequences of Operation

• Help building staff understand how the control system should operate. • Without detailed sequences, staff will have difficulty verifying correct operation and troubleshooting problems. • The sequences provided in the contract drawings and specifications provide a good overview, but they may need to be supplemented for the Systems Manual. • For example, the Systems Manual should address any critical system interaction details that the Sequences of Operation do not cover. • At a minimum, a detailed Sequence of Operations should be created for each HVAC and lighting system.

The O&M Manual Includes

• Installing contractor contact information • Product data • Test data • Parts lists • Installation instructions • Operation requirements • Preventive maintenance requirements •Troubleshooting procedures specific to the equipment design and application • Equipment submittals • Design documents • Performance curves (for pumps, fans, chillers, etc.) • Control strategies • Sequences of Operations • Copies of commissioning tests • Copy of Testing Adjusting and Balancing report • Warranty information

Building Commissioning Assessment

• Median commissioning costs: $0.30 and $1.16 per square foot for existing buildings and new construction, respectively • Median whole‐building energy savings: 16% and 13% • Median payback times: 1.1 and 4.2 years • Very considerable reductions in greenhouse‐gas emissions were achieved • High‐tech buildings are particularly cost‐effective, and saved large amounts of energy and emissions due to their energy‐intensiveness

The Commissioning Lead's Responsibilities

• Organize and lead the commissioning team • Ensure that the owner's expectations are adequately documented in the Owner's Project Requirements, Basis of Design, and Design Narrative • Review design submittals • Assist in documenting the commissioning requirements to be included in the specification • Prepare and update the Commissioning Plan • Organize and lead commissioning meetings • Develop and maintain an Issues Log • Observe construction • Observe and document functional testing • Verify that the Systems Manual is complete • Review staff training plans and materials, attend sessions, and verify that training is acceptable • Prepare and submit the final Commissioning Report • Conduct periodic site visits during first year of occupancy, conduct any deferred testing, and serve as a resource to building staff

Pre‐Design Phase Deliverables

• Owner's Project Requirements document • Commissioning Plan outline listing design phase activities

Design Phase Deliverables

• Regular commissioning progress reports • Issues Log • Comments on the Basis of Design and Design Narrative documents • Update Commissioning Plan, listing Construction Phase activities • Commissioning specifications for inclusion in the bid documents

Occupancy and Operations Phase Deliverables

• Summary report from seasonal testing • Warranty review of each system • "As operated" sequence of operations (developed either by the commissioning lead or the controls contractor) • Findings from the Occupancy and Operations Phase for inclusion in the final Commissioning Report • Final Issues Log • Final Commissioning Report

O&M Manuals

• The product of a team effort, and individual responsibilities will vary on each project. • In the most common arrangement, designers produce sections on the equipment they specify and compile the O&M Manual. • The commissioning lead reviews the manual to ensure it meets the owner's needs and may also provide a detailed outline of the manual's contents in the specifications. • It is important to note that contractors are not required to produce O&M Manual materials unless it is written in the specifications. • For manuals to be optimally useful, the specifications should include the level of detail required in the materials and their due date.

Construction Phase Deliverables

• Updated Commissioning Plan, with construction schedule • Reports of submittal reviews • Completed verification checklists and functional tests • Report of training completion • Reviewed Systems Manual, aka Operation and Maintenance (O&M) • Minutes from commissioning meetings • Issues Log • Periodic commissioning progress reports • Draft Commissioning Report

Current HVAC Systems

• Utilize sophisticated, automatic controls to attain proper fluids (air & water) for heating, cooling and ventilation in any building. • Documentation and adherence to the above procedures are essential in order for synchronization and in accordance with design intent.

Construction Phase Savings with Commissioning

• reduced change orders by 87% • contractor call‐backs by 90% • Reducing the total construction cost by an estimated 4% to 9%


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