Commissioning New And Existing Facilities: The Energy Manager’s Critical Role

by Yousef Abouzelof, facilities manager for Zions Securities Corp., Salt Lake City

INTRODUCTION

Architects and mechanical engineers specify energy-efficient equipment in their design. General contractors and their sub-contrac-tors order and install this equip-ment to satisfy the project comple-tion date. But with all of the last-minute fanfare-from painting and carpeting to the installation of building controls and fire systems- how do we really know if the speci-fied equipment has been installed and if it is operating at its expected efficiency levels? Commissioning is a process that verifies the owner re-ceives what was specified in the de-sign document. It is also the pro-cess of ensuring the complex array of mechanical and electrical equip-ment, safety systems, elevators, uninterrupted power supplies and emergency generators work to-gether effectively and efficiently. In essence, commissioning is a quality assurance program for the owner. An energy manager must be famil-iar with the commissioning process so he or she can ensure specifica-tions are being met.

Commissioning ensures a new fa-cility begins its life cycle with sys-tems that perform at optimal effi-ciency. Recommissioning or com-missioning of existing buildings can help reduce energy consumption, optimize the air and water distri-bution systems, enhance perfor-mance and improve tenants' ther-mal comfort. Recommissioning can restore a facility's performance to its initial design specifications, or make the systems work for the first time. It is a value-added process that substantiates that the new fa-cility and systems being delivered function and operate as intended by the design specifications. Commis-sioning improves a facility's asset value and assures the owner that all~ of the equipment operates at design performance and efficiency levels.

For a new facility, a review of the operation and maintenance (O&M) manuals and the start-up of a pre-ventative maintenance (PM) pro-gram will extend the life of equipment. For existing facilities, a review of maintenance practices may uncover deficiencies in the current PM program or recommend the start-up of a new PM program. Commissioning also can ensure operations and maintenance staff. receive equipment training in a timely and effective manner. Un-derstanding the proper operation of the main system as well as each~ of the system's components is critical in maintaining the integ-rity of the overall system. Remem-ber, all equipment and systems- regardless of their technological advances, complexities and auto-mation levels-will be controlled by the facility's operations staff. Training for the facilities staff is one of the most important benefits of commissioning. Because more and more facilities are installing meters and sub-meters to allocate cost and bill tenants for actual power consumption, com-missioning ensures that the configu-ration of the metering system is cor-rect and that the allocation program reflects actual consumption levels.

Types of Commissioning

There are three main types of commissioning: design-through-oc-cupancy, construction-through-oc-cupancy and existing building com-missioning or recommissioning.

• Design-through-occupancy com-missioning is the most comprehen-sive and starts with conception of the project. It continues through construction, into occupancy and beyond. Design and product selec-tion flaws can be corrected much easier during the design stage.

• Construction-through-occupancy is the most common type of com-missioning. Design specifications and project selection have been ap-proved and work is in progress. The general contractor will correct prob-lems found during the construction and start-up states.

• Existing building commissioning or recommissioning is the most challenging and rewarding because the commissioning results are im-mediate. Recommissioning can un-cover and fix existing problems or can make the systems work for the first time.

• Energy managers should use commissioning of new and existing facilities as an opportunity to im-prove heating, ventilating and air conditioning (HVAC) optimization and energy management. Energy ef-ficiency is a direct result of proper design, selection, and installation of equipment and systems. The failure of any one of these components ad-versely affects the energy consump-tion and efficiency of the facility. Energy managers should extend their horizons by including commis-sioning as an extension of energy auditing.

Elements of Commissioning

The commissioning process con-tains many elements that should be followed to make the effort worth-while. Main elements include:

• Develop a commissioning docu-ment or report that includes a list of all the systems and their components that require functional test-ing and inspection. For example, checking a cooling system will dic-tate the inspection of all of the chiller system components, namely, the chiller condenser and chilled water pumps; strainer baskets; wa-ter treatment system (both initial flushing of all piping and the regu-lar water treatment program); heat exchanger; and, most importantly, the controls system. Tracking is much easier with a well-defined list and procedures.

• Witness and document the start-up of all major systems. Witnessing the system's start-up is critical since this will activate the warranty period in most cases.

• Functional testing and acceptance of a system should begin as soon as the system is ready for inspection. Include all test results in the commissioning report, including the date of the test, a brief description of the system or the compo-nent, and if the item passed or failed. Report all items that fail the inspection directly to the general contractor. Retest all failed prod-ucts, poor installation or incorrect programming after repair or re-placement is complete.

• Point verification of the controls program. Check all analog in-and-out and digital in-and-out points. Check and verify digital input points on air handlers, pumps, boil-ers and chillers. If the specifications do not include digital inputs, install them before the tenant moves in. Review occupancy heating and cooling set points. Check the heat-ing and cooling water reset sched-ules for accuracy.

• Review the as-built documents. The more change orders issued dur-ing construction, the more critical the need for as-built documents. This is true for HVAC equipment, plumbing, electrical distribution systems, and especially electric and natural gas meters and sub-meters. Meter configuration documents should clearly indicate what is be-ing metered, not the initial design.

• Review the O&M manuals to en-sure the product description matches what was purchased and installed. The manual should in-clude actual O&M information, not advertisement and product line literature.

Review or initiate a PM program. For energy managers with a strong background in HVAC sys-tems and a full understanding of life-cycle cost analysis, this step is critical and will have a lasting im-pact on the facility.

• Oversee and document the train-ing of operations staff. A well-trained operations staff will under-stand the design and proper opera-tion sequence of various pieces of equipment. A trained operations staff will positively affect the life-cycle cost of any system or facility.

• Initiate an energy accounting pro-gram as the final step in assuring the owner that the tenants will pay their share of electric or natural gas power consumption.

Commissioning Case Studies

As an owner-developer-operator, Zions Securities Corp., Salt Lake City, has a long-term interest in im-proving the asset value of its facili-ties. Commissioning was introduced as a quality assurance service to con-firm that all new facilities would start their life cycle with systems operating at optimal efficiency and continue to perform at that level for years to come. In existing facilities, recommissioning of the HVAC, con-trols system, PM program and train-ing program was initiated to assess their status, performance and effi-ciency. The following summarizes some of the deficiencies uncovered during the commissioning of two new facilities and the recommission-ing of an existing one.

Case #1. Social Hall Plaza

The commissioning process on this new 160,000-square-foot, six-story office building began in 1995. Commissioning included the HVAC system, building controls system, variable frequency drives, fire sys-tem and emergency generator. Some of the deficiencies discovered and corrected during the commis-sioning process included:

• All 16 fan coil units were sup-plied at an improper voltage rat-ing and, therefore, were not wired in. The mechanical and electrical contractors and the controls corn-pany were aware of the problem, but it was not corrected until the deficiency was uncovered during the commissioning. o The heat tape on the condenser water lines was not wired in because the termination kit was missing. The kit was ordered and installed.
• The solid separator, a water-treat-ment tool used to eliminate the sol-ids from the cooling tower water, did not work and had to be repiped.
• The boilers and the hot water cir-culating pumps did not pass the functional test. According to the design documents, upon the failure of one of the boilers or hot water pumps, another backup boiler or pump would activate immediately to satisfy demand. The controls company corrected the problem.
• Digital input points were not in-cluded in the design specifications. Thus, the equipment status would show what the controls system was asking for, not the actual status of the equipment. Digital inputs were installed on critical equipment.
• The main bathroom exhaust fan was sized incorrectly. A new, larger motor and new pulley were in-stalled on the fan.
• The condenser for a fan coil unit with a top discharge was installed one foot away from the ceiling. The installation documents require at least three feet of clearance. The condenser kept going off until the unit was lowered.
• The building static pressure sen-sor was installed at a bad location causing the variable frequency drives that controlled the supply fans to operate incorrectly. The sen-sor was relocated to correct the problem.
• Permanent covers were in the pro-cess of being installed on the fin tubes' perimeter heating cabinets, but the entire enclosure above the tubes previously had been covered with a spray-on fire proofing. All fin tubes were vacuumed before the cover installer was allowed to re-sume his work.
• Training was conducted for the operations staff. A PM program was written and implemented. An en-ergy accounting program was writ-ten to allocate the electric power cost between the different tenants and the I common area.

Case #2. Deseret News Building

The commissioning process on this new 80,000-square-foot, nine-story office building began in 1996. Commissioning included the HVAC system, building controls system, variable frequency drives, indoor air quality dampers, fire and smoke management systems, emergency generator, uninterruptible power supply and electric meters. The de-ficiencies uncovered and corrected during the commissioning process included:

• Many hot water control valves on the fan coil units and the variable air volume (VAV) boxes were wired backward. All were corrected by the controls company.
• The boilers and the hot water cir-culating pumps did not pass the functional test. According to des-ign documents, upon the failure of one of the boilers or the hot water pumps, another backup boiler or pump would activate immedi-ately to satisfy demand. The controls company corrected the problem.
• The readout display on the boil-ers that indicates status and alarms and makes troubleshooting easy for the operations staff was not in-cluded. Two readout displays were purchased.
• A water source was not provided for the humidifier side of the two air conditioning units in the main computer room. New piping was installed.
• A VAV box with reheat coils was installed in the ceiling above the _ photo library. The VAV was moved away from that area.
• The indoor air quality dampers, providing fresh air to the build-ing, did not work as per design. The controls technician wired the dampers incorrectly. All wiring was corrected.
• The variable frequency drives (VFD) on many of the air handlers kept going off on motor current. The fan's pully and shieves had to be replaced to correct the problem.
• The design specification did not call for a domestic water pump. The upper floor restrooms did not have enough water pressure. Thus, a two pump domestic water system was installed to satisfy the domestic water demand.
• The York chiller would not load and kept tripping its 300-A breaker. The correct breaker size was 700 A, according to the manufacturer. New wires were pulled and the correct breaker was installed.
• The mechanical plans listed al of the VAV box locations and num-bers; however, the controls contrac-tor used different numbers for the VAVs. Mechanical as-built plans had to be updated to indicate the new numbers.
• The installed electric metering sys-tem had three major flaws. First, even though every tenant floor had a separate electric meter, one third of all the light tubes in the building were not metered because their power panel was supported by the emergency generator, which was not metered. Second, there was no meter on the roof's equipment room that housed the chiller, two boilers, all heating and cooling pumps and the elevators. Third, having multiple tenants on the same floor was not considered in the design. Therefore, the initial design of the metering sys-tern was incorrect. To correct the system would have required a capi-tal budget investment. Manual meter reading and billing are being used at this time.
• The tenant move-in date was the second week in May; however, sub-stantial completion payments re-quested by the general contractor were not approved until November. The owner supported the commis-sioning process by withholding "substantial completion" payments until all commissioned items were corrected. This was the only moti-vation for the general contractor to correct all outstanding items.

Case #3. Gateway Tower East

This 289,475-square-foot, 19-story office building was con-structed in the mid 1960s and is cur-rently being remodeled. The three-pipe system-one for heating, one for cooling and the third for the common return-is being replaced. Separation of the heating and cool-ing system is to be completed in stages. The leaky induction units around the perimeter of the building are being removed one floor at a time. A new controls system is being installed. The boiler plant has three new boilers, two l6-million-British thermal unit (Btu) boilers and one 1 .5-Btu boiler. New air handlers are being installed, with each air handler supplying air to two floors. As soon as a floor becomes vacant, the upgrade work begins. Commis-sioning of the HVAC system is in-tended to find out the efficiency and performance of the new system. Following are the deficiencies that have been uncovered:

• The design specifications called for the two 16-million-Btu boilers to go off during the summer time. The 1.5-million-Btu boiler was sup-posed to satisfy the domestic hot water demand of the building. Com-missioning of the boiler plant indi-cated that the entire boiler plant stayed on all year long because the water flow (gallons per minute) through the small boiler was too high. A new small circulating pump and control valve was installed at the boiler to correct the flow prob-lem during the summer months.
• The boilers were cycling on and off all the time. The "low fire was set manually on the boiler's control panel. All switches were turned on to the correct settings.
• The VFD controller on the sixth floor air handler, which was up-dated two years ago, was running at full speed (60 Hz) all the time, without being able to satisfy the tenant's cooling needs. This par-ticular air handler supplied air to the fifth and sixth floors. The air balance report indicated high static pressure at the elbow of the duct work separating the two floors. The duct work was corrected. More air is being deliv-ered to the tenants on both floors. The VFD speed has been corrected and is running be-tween 35 Hz to 40 Hz dur-ing the day.
• The chilled water supply line was piped backward to the cooling coils on three different air handlers, thus, affecting six floors. The piping was corrected.
• The chilled water flow was too low to the air han-dlers. The VFD that controlled the chilled water circulating pumps was set too low. A few years ago, the chilled water flow was set low due to the vacan-cies caused by the HVAC remodel-ing. Upon completion of the remod-eling, no one remembered to in-crease the water flow. This has been corrected.
• Commissioning uncovered a seri-ous problem with the software main-tenance of the controls system. Since the entire HVAC system is being upgraded one floor at a time, quite a few pieces of equip-ment are being added, replaced or eliminated. Consequently, many control points have been inacti-vated or disconnected from the equipment. According to the front-end computer, these points were still active, showing status and temperatures because they were never deleted from the controls system. The operations staff was not sure which points were real and which were not. The controls company was asked to conduct a software maintenance audit on the system and then the system will be re-evaluated.

CONCLUSION

According to the Oregon Office of Energy, studies on commission-ing show average energy savings of 15% to 30%. Over the years, en-ergy managers have been busy lowering the energy consumption of their facilities by introducing energy efficient lighting, direct digital controls, thermal energy storage and other technologies with impressive results. Commis-sioning and recommissioning should be used as an energy man-agement tool to optimize perfor-man c e, improve efficiency and lower energy consumption.

Reprinted with permission from the author, Yousef Abouzelof, facilities manager for Zions Securities Corp., Salt Lake City. He has a master's degree in econometrics from the University of Utah. He is a member of the Association of Energy Engineers and is a certi-fied energy manager. With 20 years of experience in operation, maintenance and energy manage-ment, he has commissioned three office towers totaling 750,000 square feet and a 344 unit apart-ment complex. Currently, Abouzelof is commissioning a new 310,000-square-foot office tower.

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