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Commissioning: Forwarding The Retro Process

Further Benefits Await Beyond the Equipment

In my October 2007 column, I wrote about the importance of the commissioning professional gaining the respect, confidence, and trust of the operations & maintenance (O&M) staff during a retrocommissioning process. This will lead to more comprehensive and reliable results, the benefits of which will last longer than if the O&M staff is either uninvolved in retrocommissioning or sees the commissioning professional as an adversary. 

In the interest of even more sustainable results, I would like to suggest some deliverables the commissioning professional may want to offer the building owner as part of the retrocommissioning package.

Systems Documentation

In many cases the most reliable source of current systems operation is the O&M staff’s undocumented knowledge, and that knowledge is often mistaken in a few facts regarding control sequences, schedules, setpoints, etc. In the course of performing an excellent retrocommissioning study, the commissioning professional will extract that knowledge and supplement it with the results of field testing and trend logs.

I believe that with just a bit more effort (i.e., cost) the commissioning professional can develop a comprehensive Systems Manual that documents actual system configuration, controls, and important notes about system performance or unique requirements. At a minimum, the Manual would include for each system:

  1. Description of the system’s purpose

  2. Schematic diagrams showing all system components and their physical relationship to each other

  3. Narrative control sequences for all modes of operation

  4. Control system setpoints for optimal (per the retrocommissioning process) performance

  5. Recommendations for regular preventive maintenance (PM) activities to maintain optimal performance

The PM recommendations should not necessarily be a repeat of PM requirements for the individual pieces of equipment; something the O&M staff should be doing already based on the equipment O&M manuals provided by the original installation contractors.

However, depending on the age of the systems and the quality of the original installation and/or training, there may need some of this, if the commissioning professional finds that equipment PM procedures have not been diligently performed. The primary intent of the Systems Manual PM recommendations is to focus on checking the interface between system components; i.e., communication between control system devices, pneumatic signal integrity, shared device reliability (outside air temperatures, outside air pressures, etc.), sequencing of devices, etc.

This Systems Manual would be a valuable resource for future reference by new O&M staff or engineering consultants and as a quick refresher for current O&M staff who may not regularly work on certain systems. The format in which this information is compiled can vary from a standard bound hard copy report, to a searchable electronic format, to new screens tied into an existing graphic interface at an operator’s workstation. Ideally, but more complex (i.e., higher cost), the Systems Manual would be easily update-able as O&M staff continue to fine tune system performance and/or as system modifications are made during renovations or retrofits.

Systems Training

If a Systems Manual is developed by the commissioning professional, the obvious next step would be to have the commissioning professional conduct a Systems Training session. This additional investment (minor in the grand scheme of the entire retrocommissioning program) would be intended to introduce the O&M staff to the new Systems Manual in order to help prevent its becoming just another book gathering dust in the maintenance office.

For the O&M professionals who had worked with the commissioning professional throughout retrocommissioning, this Training should be a summary of what the O&M professionals learned as a result of their participation. For other O&M staff in the same facility the Training should be an efficient and consistent method of sharing the knowledge gained through the retrocommissioning process.

Occupant Orientation

Finally, in some cases, the building owner may find it beneficial to provide a summary of the retrocommissioning process to the occupants of the building. There may be public relations reasons for sharing the fact that the building owner brought in an outside professional to address building systems performance and efficiency, especially if the retrocommissioning process resulted in improved conditions for the occupants or reduced costs.

Another sound reason for holding such an Occupant Orientation session is to inform the occupants regarding what they can expect from the retrocommissioned systems, e.g., temperatures, humidities, air quality, etc. At the same time, this session could be a forum for educating the occupants about what they can/need to do in order to sustain optimal system performance, e.g., close doors, limit thermostat setpoints, turn off lights, etc.

 

Commissioning: Getting It Right

Engineered Systems, November, 2007

by
Rebecca Ellis, PE, LEED AP, CCP, CxA
President
Questions & Solutions Engineering
1079 Falls Curve
Chaska, MN  55318
rteesmag@QSEng.com