ing Existing Equipment

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Commissioning Existing Equipment and Systems

Overview

Commissioning existing equipment or systems can provide impressive benefits towardsimproving building operations, tenant comfort, energy use reduction and increased equipmentlife. Generally, the primary objective of commissioning existing equipment is to bring thesystem or equipment back to its original intended operation, subject to any legitimate changesmade since installation. In addition, adjusting the way systems are operated to improveperformance is also an objective.

The cost-effectiveness of commissioning existing equipment can be relatively high, when theeffort focuses on equipment that uses the most energy and/or larger pieces of equipment. Whenthe more numerous and small zone-level equipment is included in commissioning, however,commissioning can easily become quite expensive. For this reason, most commissioning effortsinclude only those systems and equipment that have the most opportunity for improvement

without large capital outlays. This toolkit is primarily focused on commissioning newinstallations, but the following provides some guidance on commissioning existing equipment.The first section provides a list of the parts of the Model Commissioning Plan and GuideSpecifications that can be used when commissioning existing equipment. The second sectionprovides an overview of actual site procedures to follow when commissioning or tuning upexisting equipment.

I. Applying the Model Commissioning Plan and Guide

Specifications to Existing EquipmentThe Model Commissioning Plan and Guide Specifications was intended for new construction orlarger building renovations. However, there is material contained in that document that can beused in commissioning existing equipment and systems. This material includes the followingitems:

Solicitation for Commissioning Services

Commissioning Firm Experience and Commissioning Project Experience Listing(Exhibits 4, and5, under Part I, Commissioning RequirementsDesign Phase) can be used when obtaining theservices of a commissioning firm.

Design Narrative

Design Documentation Format, (Appendix I, under Part II, Model Commissioning PlanDesign Phase) can be used to provide format to the development or recreation of the originaldesign intent of existing equipment or systems.

Commissioning Existing Equipment and Systems 1

Oregon Office of Energy Commissioning Toolkit 38819144.doc


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Prefunctional Checklists

Commissioning or tuning existing equipment and systems entails evaluating their currentcondition. The prefunctional checklists (found in Specification Section 15998 of Part III) forvarious equipment types can be used for this purpose.

Testing Requirements

Specific test requirements that may apply to the equipment in your building can be found inSpecification Section 15997 for mechanical systems and Section 16997 for electrical systems (inPart III, Guide Specifications). These can be used when developing the scope of work for thecommissioning and for the development of the detailed commissioning plan.

Sample Functional Tests

Though only samples, the tests provided in Sections 15999 and 16999 of Part III can be used bythe commissioning agent for reference for developing formats, content and rigor for the actualfunctional tests of existing equipment.

Functional Performance Testing

Guidance regarding the development of test procedures and acceptable test methods found inPart III, Section 17100, 3.6, applies to both new and existing equipment.

Forms

Many of the forms found in Appendix 1 of Part IV, Commissioning PlanConstruction Phase,can be used for existing equipment commissioning. These forms include a CommissioningIssues Log, Request for Documentation, Commissioning Memorandum, Commissioning Requestfor Information, Commissioning Progress Report, Staff Training Plans, Detailed CommissioningSchedule, Facility Staff Participation in Commissioning, Functional Testing Scope Outline.

II. Procedures for Commissioning Existing BuildingEquipment and Systems

This section outlines suggested steps for commissioning existing equipment. It assumes that abuilding has been selected and a commissioning agent is hired. It also assumes that an objectiveof commissioning is to reduce energy waste and therefore outlines the site activities specific toobtaining energy savings. This section does not cover the initial building selection process.

Planning Phase

1. Identify and Communicate the Primary Objectives for Commissioning the Building or

Systems

It is important to understand exactly what the objectives are for putting a building or buildingsystem through the commissioning process and to clearly communicate those objectives to thecommissioning agent. It also may be important to have measurable objectives in order todemonstrate the effectiveness of commissioning. The commissioning process may focus on oneor several of the following objectives:

Reduce comfort calls




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Increase equipment life Obtain energy savings Improve indoor air quality Reduce staff time spent on emergencies Increase the asset value of the building Retain tenants

2. Obtain a General Overview of the Building and Systems

The commissioning agent performs a walk-through of the building to obtain a generalunderstanding of what system types exist, how the systems are controlled and what the buildingis used for. It is also important to identify which systems, equipment, and groups of smallerequipment controlled together are the largest energy users. To expedite this activity, compile abuilding documentation package for the commissioning agent to study prior to the walk-through.This packet may include the following:

Drawings relevant to the systems scheduled for commissioning O&M manuals TAB report Equipment list with nameplate information PM logs Sequences of operation Energy efficient operating strategies Energy bill (electric and gas) information for at least 12 months along with a rate schedule

3. Develop the Building-Specific Commissioning Plan

Once the commissioning agent and building staff have clearly defined the objective forcommissioning and have reviewed the documentation, the commissioning agent develops thecommissioning plan. The plan includes the following information:

Commissioning objectives Scope of commissioning Commissioning team members and their roles and responsibilities Schedule of commissioning events Scope of testing Description of diagnostic monitoring and use of energy management control system trending List of products resulting from the commissioning effort

Investigation Phase

4. Perform an Operation and Maintenance (O&M) Site Assessment

The goal of the O&M site assessment is to gain an in depth understanding of how and why thebuilding systems and equipment are currently operated and maintained. For large and complexbuildings and systems the commissioning agent generally develops a formal assessmentdocument that includes a detailed building staff interview and an in-depth site survey ofequipment condition. To expedite the assessment process, assign a building operator to workwith the commissioning agent. The designated operator should be someone who is quite




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knowledgeable in operating and maintaining the systems designated for commissioning. Theassessment should identify some of the following issues:

Current design and operational intent and actual control sequences Equipment condition issues (broken dampers, dirty coils, sensor calibration, etc.) Current schedules The most severe control and operational problems Where the most comfort or trouble spots are in the building

It may be cost effective to have the assigned building operator make minor adjustments andrepairs as the site assessment progresses.

5. Develop a List of O&M Deficiencies/Opportunities

Concurrent with the O&M site assessment, the commissioning agent begins to develop a masterlist of O&M deficiencies or improvements for possible implementation. This list will ultimatelybecome an important decision making tool for the operating staff and is a primary product of thecommissioning effort. Every finding from the assessment and from the diagnostic monitoringactivity (see #6 below) is placed on this master list including those adjustments and repairsmade during the assessment process. The list includes the name of the system or piece ofequipment involved, a description of the deficiency or problem, and a suggested solution.

6. Develop and Implement a Diagnostic Monitoring Plan

Using the information gained from the O&M site assessment, it may be necessary to obtain morecomplete and exact data on when and how systems are actually operating since the assessmentmay only identify suspected areas for improvement. The commissioning agent develops andimplements a diagnostic plan for using either the buildings energy management control systemtrending capability (this is acceptable as long as the systems sensors have been recentlycalibrated) and/or portable data loggers. It is generally recommended that data be gathered for aminimum of one week including a typical weekend. Once the data is gathered, thecommissioning agent analyzes the findings and checks it against the O&M assessmentinformation for discrepancies. Any deficiencies are added to the master list described abovein #5.

7. Functionally Test Systems and Equipment

It may be necessary to manually test the system or equipment in question during theinvestigation process. Functional testing may be done as a part of diagnostic monitoring or inlieu of diagnostic monitoring. When data loggers are not available or the energy managementcontrol system is inadequate for trending, functionally testing the system manually is the onlyoption. Manual testing involves putting the system or piece of equipment through a series oftests that checks its operation under various modes and conditions. Spot measurements are takento verify correct operation and equipment efficiencies.




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Selection / Implementation Phase

8. Determine Which O&M Opportunities are Most Cost Effective to Implement

Once the investigation process is complete, the master list of O&M opportunities is used to

decide which improvements are most important to implement. As part of the selectionprocesses, it may be necessary to do some engineering analysis to determine which opportunitieswill save the most energy and cost the least to implement. It is not unusual to expect a simplepay back of 18 months or less for the selected improvements.

9. Implement O&M Improvements

The overarching goal for commissioning existing building systems is to implement cost effectiveimprovements. Unless improvements are actually put in place, the commissioning processremains incomplete. Depending on staff time and expertise, the implementation process may becarried out by in-house O&M staff. In some cases implementation may need to be outsourced.

For example, hiring a controls contractor may be necessary if in-house staff lacks the expertiseor access required to make control strategy changes at the program level.

10. Supervise the Implementation Process and Retest as Needed

It is often important to retain the commissioning agent through the implementation processwhether implementation is done in-house or outsourced. The commissioning agent maysupervise those tasked with installing the improvements depending on the level of complexity.Also, it is often necessary (and highly recommended) to retest some of the equipment andsystems, either manually or through diagnostic monitoring, to ensure that the improvements areworking as expected and that they positively effect other systems and equipment as well as thebuilding occupants.

Project Hand-Off Phase

11. Identify Possible Energy-Efficient Capital Improvements.

During the normal course of commissioning , review current equipment and system efficiency,condition and age not only for O&M improvements but also for future energy-efficient capitalimprovements. Although the existing building commissioning does not involve implementingexpensive energy-efficient capital improvements, it is often the first step toward obtaining theseimprovements. It is therefore important for the commissioning agent to recommend a list ofrelevant energy-efficient capital improvements as part of the project hand-off. This list mayinclude the following:

Energy-efficient lighting retrofit (interior and exterior lighting, exit lighting, etc.) Addition of lighting sweep controls Daylight harvesting Variable frequency drives CO2 based ventilation control




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12. Commissioning Final Report

The commissioning agent prepares a comprehensive final report that generally includes thefollowing information along with an executive summary:

Project background

Building / systems description Scope of the commissioning project The master list of improvements A description of which improvements were implemented and a cost/savings analysis List of recommended capital improvements The original and corrected commissioning plan The EMCS trending plan and logger diagnostic / monitoring plan and results All completed functional tests and results

Acceptance of the final report by the building staff or owners representative concludes theproject hand-off phase

Other Commissioning Tasks for Contract Consideration:

1. Finalize an O&M plan outline, including examining and enhancing the currentmaintenance service contract procedures.

2. Develop a list of required O&M documentation and methods for the building orsystems. Include full written sequences of operation for all equipment.

3. Develop an energy efficiency plan and policy, including strategies for obtainingmanagement buy-in.

4. Develop guidelines for implementing a preventative maintenance plan.

5. Develop a comprehensive training plan. Or, develop recommendations for appropriatebuilding staff to attend training in general O&M concepts and for specific equipmentand systems. This will include both building operators and facility managers orowners.

6. Develop guidelines and recommendations for incorporating an energy accounting andtracking system.

7. Develop a list of operational strategies for the owner to incorporate in the future.

8. Develop an operations assessment program and systems tune-up and recommissioningschedule.




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Reference Documents

An excellent book that details the process of tuning up existing equipment for energy efficiencyis,Energy-Efficient Operation of Commercial Buildings: Redefining the Energy Managers Job,

Peter Herzog, McGraw-Hill, 1996.



ing Existing Equipment

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