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Article - Jan 2000
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Control Solutions, Inc. - Minnesota

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Viktor Boed, CEM
Yale University
New Haven, Connecticut
a consulting engineer, who also designed automation systems in Europe and USA. 


Overview

Comfort, safety and economical operation of modern buildings is controlled and maintained by environmental control systems. Environmental control systems in buildings are (1) Heating, Ventilating and Air-conditioning systems or HVAC and their supporting systems, and (2) Building Automation and Control Systems or BA(C)S. BAS systems (the most commonly used abbreviation) are the brains of the environmental control systems. They operate and monitor the connected HVAC systems by series of programs and also provide information on the building environmental conditions to the building operation and maintenance personnel, and/or directly to the customers.

It should be noted that environmental systems alone can seldom provide adequate environmental conditions if they are designed as "afterthoughts" to the architectural design. To assure the desired environmental conditions at all load and occupancy conditions (during the four seasons), the building has to be designed from the early program development phase with the end goals in mind - which is occupancy comfort, safe, reliable and economical building operation. Architects, mechanical and control engineers should, as one team, be participating in the entire design, installation and turn over with the building owner to deliver a fully operational building to the building occupants.

One of the ways leading to efficient systems implementation is a method called Total Commissioning and TQM process. (See Viktor Boed: Controls and Automation for Facilities Managers - Efficient DDC Systems Implementation, CRC Press, 1-800-272-7737, Cat. No.: CH 7229). As part of the implementation process, project managers can utilize checklists as a management tool to assure orderly conduct during individual phases of the project. Checklists listed in the above book contain items that require attention at each phase of the project, as well as engineering tips from design development through final walk through. Individual checklists were developed for each phase of the project and can be used throughout the entire system implementation process.

Reliable Controls Checklists are valuable tools and are used in many critical operations. You have probably seen through an open door of a commuter airline pilots doing their pre-flight checks with checklists in their hands - a process they do before every take-off, during every flight. Not that they would not remember which instruments and switches to check, but to assure that all the important items are checked in a proper sequence. They repeat the process throughout the most important phases of the ground and flight operations. Some (prudent) construction managers use checklists for recording and comparing bid items and other activities during bid evaluation of multiple vendors.

For environmental control systems implementation, checklists should be developed for every phase of the project - design, installation and commissioning. This approach also encourages teamwork throughout the entire process, which results in a design that contains inputs from mechanical, controls and facilities engineers. It will optimize the use of architectural, mechanical and controls systems in the building, and minimize the cost for engineering change orders throughout the implementation process. Change orders are the way of life. Checklists and systemized approach will keep the cost for change orders to the minimum, by implementing the changes at the early stages of the project. Focus on quality, systematic approach and the use of checklists will result in delivering a building to the owner, which will maintain designed parameters under all load conditions reliably, and assures optimum first cost as well as operating cost throughout the life cycle of the building.


Fig.1. Cost increase escalation for changes during project phases

Checklists as Quality Assurance (QA) tools.

As said before, checklist should be used as tools to assure quality at every step of systems implementation. Since buildings and systems are "custom made" checklists should be also "custom made" for the given project. However, every checklist contains generic items that along with job specific items can be used for a given job.

Since the article can not list all the checklists, the following is a compilation of selected checklists and items that have the most impact on building design and performance. They are divided into three basic stages - design, installation and commissioning. A full section of activities (and checklists) related to DDC system selection, design, software development, installation, testing and validation is left out from this article. Nevertheless they deserve attention since they are often the least understood by architects, consulting engineers, construction managers and owners.

Checklists for design phases of the project.

A project design phase can have several phases, from program definition phase through design development to construction documentation, depending on the job. Since the design phase shapes the future building and its systems, team work of the participating engineers and agencies as well as clear definition of the goals for building performance is utmost important. Three disciplines that have the most impact on the performance of environmental control systems are: Architectural - HVAC - BAS.


Fig. 2. The three disciplines of a successful design.

Occupancy comfort of buildings is judged by building occupants. Consequently, building owners and managers are interested in having satisfied tenants. In addition, they are also interested in safety, systems reliability, and efficiency of building operation. These should be the design goals set for the design and implementation teams.

Items having the most impact on achieving the above goals, divided into the three disciplines are:

ITEMS DATE OF SUBMITTAL APPROVED    NOT APPROVED  DATE OF RE-SUBMITTAL QUALITY RATING
Building location          
Design for local conditions          
Building envelope          
Windows          
Doors          
Loading docks          
Air intakes          
Air exhausts          
Space assignment          
Zoning          
Design for the needs of occupants          
Zone/room design parameters          
Mech. Rooms          
HVAC equipment locations outside of MRs          
Horizontal and vertical chases          
Service access          
Task lighting          
           
Job specific items          

Table 1. Checklist for architectural design

HVAC design has to compliment the architectural design and provide the desired heating, cooling, ventilation and safety. It also have to assure economical and reliable operation to keep the operating cost at the minimum level. HVAC design features having the most impact on the environmental control systems design and performance are:

ITEMS DATE OF SUBMITTAL APPROVED NOT APPROVED DATE OF RE-SUBMITTAL  QUALITY RATING
Design parameters for zones and building          
Sizing of the HVAC equipment          
Heating          
Cooling          
Ventilation          
HVAC systems          
Ductwork          
Piping          
Air intakes          
Air exhausts          
Zoning          
Zone/room design          
Equipment layout          
Mechanical spaces          
Interface w/other HVAC systems          
Chill water interfaces          
Steam/condensate connections          
Electrical connections          
Energy efficient lighting          
Energy efficient motors          
Free cooling          
Heat recovery          
Design for IAQ          
Design for site standardization          
Maintenance requirements          
Training          
BAS interfaces          
           
Job specific items          

Table 2. Checklist for HVAC design

BAS design has to provide the operating logic, alarming and reporting requirements and to meet the level of desired automation expected by the owner. Today's Direct Digital Control (DDC) systems are more then just a bunch of single loop controllers in one box. The owner pays for a "full" DDC system and expects to get one with all available controls and automation capabilities. BAS application engineers should be part of the design team. Their contribution could reduce the HVAC system cost and result in better overall design. The BAS system design should include:

ITEMS DATE OF SUBMITTAL APPROVED NOT APPROVED DATE OF RE-SUBMITTAL   QUALITY RATING
Review of design parameters for zones and building          
DDC system architecture          
Heating control          
Cooling control          
Ventilation control          
HVAC systems control          
Sensors/actuators in the ductwork          
Sensors/actuators in hot water/chill water piping          
Damper control          
Zoning control          
Room control          
Equipment control          
Chiller control          
Boiler control          
Building pressure control          
Utility metering          
Electrical metering          
Lighting control          
Free cooling          
Heat recovery control          
IAQ          
Site standardization          
Networking          
Interface to facilities systems          
Interface to other BAS          
Interface to building controllers          
Maintenance requirements          
Training          
PMI interfaces          
           
Job specific items          

Table 3. Checklists for BAS design.

Checklists for installation phase of the project.

The approach to Total Quality Management, and the use of checklists is an excellent management tool in this phase of the project. The installation (construction) phase of larger projects are usually managed by professional construction management firms. They have their ways of coordinating job activities and job schedules. Scheduling of individual trades and their coordination is probably the greatest challenge during the installation phase. Larger and smaller jobs alike can benefit from systemized approach to management.

During the installation phase the focus should be on:

The above items are often omitted from the process unless there is an owner's appointed commissioning agent or inspector for the job. Nevertheless, they are important for quality of installation and for operation of the installed systems. Many "shortcomings" (and we know there are some on every job in effort to meet deadlines) become invisible since the components are hidden behind walls, ceilings and in other building cavities closed in as the job nearing completion. They, usually, show up later as maintenance items (nightmares) after the job is turned-over to the owner. The cost for "fixing" these problems is then much higher then it would have been if discovered during installation. Also, the cost associated with these problems burden the O&M department, which usually does not have construction (nor start-up) related costs in their budget. Most importantly, the building occupants, who expected to move into a new comfortable and trouble-free building are inconvenienced by problems originating from systems installation (or design).

Progressive inspection of the construction site by the O&M personnel, is important for several reasons: First, the owners O&M personnel familiarize themselves with the location of individual components - very important for time optimization when responding to emergency or routine maintenance calls. Second, the O&M personnel develop feeling of "ownership" to the building even before completion of the job. Over the years we have experienced high level of acceptance of jobs by the O&M personnel when they had a chance to participate in field inspections and/or in custom development of graphical DDC screens, alarm definitions and other job related activities.

Due to the limitations of this article only one checklist, for DDC installation, is presented as an example. However, construction, project and facilities managers should develop other checklists for mechanical, HVAC, electrical and other installations.

ITEM      Approved
(Y/N)
Not 
Installed
Install by
 (Date)
Mechanical
Installation
Electrical
Installation
DDC hardware locations, workmanship, accessibility, labeling, check reference values (V, mA, Ohms), set up values, switch and jumper settings, etc.          
Outside air sensor          
Space sensors (list T, RH, P, etc)          
Duct sensors (list all)          
Hot/chill water sensors          
Control valves and actuators          
Dampers and actuators          
Meters and their electronics          
DDC controllers          
Field equipment panels wiring, labeling, termination          
Grounding          
Wells and taps          
Gauges          
Valves          
Dampers, louvers          
In-line meters          
Insulation          
Labeling          
Task lighting          
Power supplies and transformers          
Motor control, switches, relays          
Communications hardware
         
Communications wiring          
Grounding          
Job specific field hardware          
           
Application software-controllers: (check addresses, responses, values, comm. drivers, etc.)          
Loading into controllers          
Compliance with the point list          
Compliance with the sequence of operation          
Set point values          
Alarm values          
PID loop values          
Communications set-up          
Field protocol with initial values          
Job specific items          
           
Application software-OWS:          
Setting-up the front end          
Loading the front end software          
Loading the comm. software          
Loading the graphic software          
Point binding          
Checking alarm, history and other files          
Job specific items          
           
Documentation: (Corrected for as built conditions)          
Point list          
Controls schematics          
Initial set-up values          
Hardware, software job specific documentation, including applications software          

Table 4. DDC installation checklist

Checklists for commissioning phase of the project.

Environmental system commissioning is a complex task. Systems commissioning should confirm:

  1. the installed systems meet design parameters,
  2. they are properly installed and set up,
  3. they operate properly under various operating conditions,
  4. they interact and are interoperable with other systems,
  5. provide the owner with a set of start-up operating values - a very valuable information for future system maintenance
  6. provide instructions to O&M personnel on how to operate the building.

There are a number of contractors (disciplines) involved in commissioning under the three basic groups:

The owners O&M personnel should be fully involved in this stage of the project. They should be part of setting up a commissioning plan, witness functional and performance testing, validation and verification of systems operating parameters. They should verify operation of the installed systems under normal and emergency conditions, during shut-downs, start-ups, etc. They should receive operator training and as build documentation prior to final acceptance. They should be involved in post-acceptance systems performance verification for a one-year (four-season) systems performance warranty.

The commissioning documentation should be part of the acceptance documentation package and should aid the owners O&M personnel in future maintenance and systems calibration.

The following example is a short version of a checklist for hot water exchanger commissioning.

Device  Model# Serial#  Type  Design Parameters  Manufacturer
Exchanger          
Control Valves          
Steam Traps          
DP Valve          
Pumps          
Motors          

Table 5. Nameplate Data

Item Hardware
Software
 Device Model End-to-end
Accuracy
Set-point
Value 
Alarm Limits
High/Low 
Remarks
HW Supply Temp            
HW Return Temp
           
Differential Pressure            
Steam Valve 1/3            
Steam Valve 2/3            
Steam Trap            
Condensate Temp            
Pump 1 VFD            
Pump 2 VFD            

Table 6. DDC Data Checklist

Item  Operation 
Verified
Set-points
Constants
Alarm limits
Operating
Interface Trends
 Documentation  Re-test date
(if failed)
HWX Temp. Control          
HW Pump Control          
HW DP Control          
Condensate Alarm          
Reset Schedule          
Alarm Reporting          
Operator Advisories          
Emergency Shut-down          
Job Specific Items          

Table 7. Demonstration of control loop sequence of operation for normal and emergency conditions

Conclusion.

Checklists from design/ implementation phase of the project serve the project management during the implementation phases of the project. They provide important information to the owners O&M personnel long after completion of the job. As part of the turn-over documentation they become a resource for building maintenance for re-testing and re-calibrating the building operating parameters. They are a good source of information for years after a job completion for design engineers involved with building, systems or space renovation of the building.



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