Commissioning lessons from the field

These are five lessons learned from commissioning projects. Anyone new to commissioning can learn from these tips.

By Derek DeJesus, CxA, LEED AP, BD+C, KJWW Engineering Consultants, Chicago June 23, 2014

More than 15 years ago, I was sent on my first assignment to witness the load bank testing of a generator. Like so many young commissioning agents, I was diligent in reviewing the project specifications and code before writing my functional test procedure. I knew I would have to defend my position for the requirements and document the EPSS performance. I felt confident, knowing that the test procedure I was using had been written months earlier, issued for the team to review, and scheduled with the contractors.

I had no way of knowing I was about to enter a very adverse environment where I would have to negotiate with the AHJ.

The general contractor, electrical contractor, vendor representative, AHJ, and building owner were already at the trailer when I arrived. I had rehearsed the test in my head and thought about all the different data and observations I needed to make in the short amount of time we had to perform the test. I had written portions of the functional performance test based on the NFPA 110, Chapter 7 requirements that were specified in the project manual. The requirements were clear to me, and I assumed the others understood and agreed because no one had commented when we issued our test for review.

Commissioning lesson No. 1: Not all of the members of the team review and comment on functional tests.

Just because it is written does not mean it is understood. Thankfully, as part of our preparation for the testing, we had called ahead to ensure that all parties would be present at this test.

This was the second trip for generator start-up by the vendor and the one that would conclude our functional testing. It also included the load bank testing, alarm verification, and operational testing that included the ATSs. Some of the NETA testing had taken place a week earlier, and during this visit with the vendor’s start-up technician, I had shared with him my functional test procedure—the first time he had seen this document.

Lesson No. 2: Not all team members actually receive the commissioning documentation.

The start-up technician’s boss had received the documentation, but this tech had just been assigned this project through dispatch. I kept my distance, but made subtle observations and communication with him throughout his start-up. I felt comfortable sharing this test with him so that on the next time out, he would remember me and have a better understanding of any load bank testing that was required.

Lesson No. 3: What is purchased and what is done in the field is not always what is required by the project.

A week later, as I entered the project trailer, I was welcomed with a “be quiet” finger-across-the-lips motion by the general contractor as a conference call related to load bank testing was taking place. As the person on the phone finished speaking, the contractor announced that the “commissioning guy is here now, so let’s get his opinion.”

It turned out that the generator manufacturer’s project manager had only sold 2 hr of load bank testing and was wondering where 4 hr plus a 100% single-step load had come from. I calmly read off the specific code references I had inserted into my functional test.

By referencing code sections (or even specification sections) in your functional test, everyone should know what you are talking about if you ever have to explain yourself. This turned out to be one of those times, however, in which I had to not only decipher the code, but also play peacemaker between all the parties around the table. What I thought was a problem with my test procedure turned out to be a problem in coordination.

A week earlier when I had given the functional test to the start-up technician, he actually did read it. He thought it was well organized and pretty clear except for the time requirements, which stated he needed to perform load bank testing for more than 4 hr (his purchase order told him it was a 2-hr test). So he raised the concern with his scheduler, who contacted the project manager, who contacted the electrical contractor, who did not contact anyone else.

Lesson No. 4: Just because you think you are ready does not always mean everyone is ready.

If you want to add value and help in coordination, then reach out to all interested parties prior to the testing to ensure everyone is ready. Needless to say, the AHJ in the room did not have a strong opinion either way, but believed 2 hr was long enough. In addition, the owner was not technically savvy enough to know what he would learn after an additional 2 hr.

Not wanting to compromise the integrity of my test, I stood my ground as best I could. In the end, the AHJ changed his stance, which, as well all know, changes everyone’s stance.

As a team, we then stepped through the entire functional test to ensure we all understood what was expected at this time. After a few minutes of page flipping and head nodding, we headed out to the generator room and began our test.

After 2.5 hr of testing, I went to the roof of the eight-story building to inspect the generator exhaust stack. (The generator had been installed in the lower level of a wing, and the exhaust stack ran through the interior of the building, encased in a shaft, until it penetrated the roof.) As I exited the stairwell door and made my way to the exhaust stack, I noticed steam or smoke emerging from under the roof flashing next to the stack. I called down for the general contractor, who, knowing something was amiss, removed the flashing.

We discovered that a subcontractor had braced the exhaust stack, which can reach temperatures of 800 F, not with steel, but with wood, which was now smoldering.

Lesson No. 5: Not everyone follows code on a project.

This lesson is one of many I apply today on my site inspections and use as an argument if I have to defend the requirements of the NFPA or the commissioning process.


Derek DeJesus is the national commissioning manager and electrical commissioning leader for KJWW Engineering Consultants. He supports the company’s commissioning business development, project oversight, and commissioning program.