There are seasoned contractors, engineers, and technicians who are not even aware of commissioning. Others don't understand what it is truly about.

Why in the world then should I discuss this concept in a forum meant to address HVAC basics?

Because when a fundamental knowledge of commissioning is applied, it could potentially enhance your customer's comfort and safety needs while simultaneously lowering their utility bills. It will also make you a better technician and enhance your wage earning potential, separating you from less skilled technicians groveling for more than cost-of-living wage increases.

Defining The Term

Before we break down the commissioning mindset, let's take a look at a good industry definition of commissioning from Rebecca Thatcher Ellis, P.E., vice president of Sebesta Blomberg and Associates.

"Commissioning is a systematic process of ensuring, by verification and documentation, from the design phase to a minimum of one year after construction, that all building or facility systems perform interactively in accordance with the design documentation and intent, and in accordance with the owner's operational needs, including preparation of operation personnel."

A typical residential replacement project might go like this: Assuming a salesman has already assessed his customer's needs and designed a good working solution and the customer accepts, the next step is to communicate the design intent to his company. (On larger projects, the salesman might even consult with the installation technician in the design phase prior to the proposal.)

Eventually, this information comes to the installation technician by way of the work order. The specifications include equipment, accessories, and ductwork modifications. Once the equipment is installed and modifications are performed, the installer will go over a checklist to make sure the system is operating.

Applying the commissioning mindset to this example, we will pick up at the work order. In addition to including equipment, accessories, and ductwork modifications, it will include details on system operation and performance. For instance, it might detail how many cfm the unit is supposed to produce in high-speed blower mode, as well as the cfm at each register outlet.

Some of this information will come from the equipment installation instructions and some will be salesman generated. Following installation, the technician should document system performance measurements and verify that everything is operating at the design intent.

The next step is to educate the operation personnel, in this case the homeowner, about the operation of the system. This will include verbal instructions and maybe even an operations manual produced by the manufacturer.

Tips To Remember

Residential installation keys to the commissioning mindset include:

  • A crystal-clear understanding of the customer's requirements.

  • Razor-sharp internal company communication.

  • A detailed work order including performance characteristics.

  • Documented performance measurements.

  • Educating the homeowner.

    Ask Yourself This

    When the job is completed, consider these questions: Is the system working the way you told the homeowner it would? And is it working according to the way it was designed? Have you documented the information? And have you taught the homeowner how to use it?

    The Service Tech's Viewpoint

    Although a service technician is generally not involved in the formal process of commissioning, he can benefit immensely from applying the commissioning mindset. In fact, most top technicians apply some, if not all, of the mindset already.

    In order to repair equipment or system problems, a service tech must know how the system is supposed to work in the first place. The commissioning mindset encompasses not only the sequence of operation, but the desired set points and run parameters along the way.

    This data is then documented. A typical worksheet might have a design intent column, for instance, how many volts are supposed to be present, and then another column for the actual measurement. Over a period of time, after preventive maintenance checkups, the technician can analyze the information and detect potential or existing problems.

    The day will come when improved technology and more educated business owners can make the commissioning mindset commonplace. Until then, be aware of how the system is supposed to operate, make your repairs or install the system, document the operational data, and clearly inform the homeowner on the repairs you made or the operation of the system.

    Rothacker is a member of the National Comfort Institute's Advisory Board and a National Comfort Team Founding Member. For questions or comments on Tech Basics, contact Rothacker at

    Publication date: 12/15/2003