Retrocommissioning Can Overcome Operational Challenges
Retrocommissioning can help a facility's performance by making up for procedures that might not have been performed properly at the time the building began operation. At times, building owners omit or minimize proper test-and-balance or commissioning processes from the initial startup of a facility, due to cost considerations or other reasons.
For example, in one facility with a three-stage cooling system, the manufacturer's representative never started up or tested the chiller, or actually put it into service. No one noticed the chiller's absence, due to an unusually cool summer. As a result of the oversight, the representative had to return to the facility the next season to complete the work and retrocommission the system — at a higher cost.
Retrocommissioning also can bring additional operational issues and opportunities into the open.
For example, a utility service area recently changed the makeup and, therefore, the heating value of its natural-gas supply. This change required updates to facilities with older burners on fuel-fired equipment. Left unchecked, wasteful or potentially dangerous conditions related to the burners could remain and present a threat. Retrocommissioning the fuel-burning systems not only allowed managers to update the system. It also enabled technicians to discover additional opportunities for energy-efficiency improvements.
In another example, a controls contractor updated the software for a facility and removed all of the updates to the control sequences. The building owner initially thought the system's poor performance and inefficiency arose from its design. Through retrocommissioning, technicians discovered the change the contractor made to the controls software and corrected it, improving operational performance.
Retrocommissioning looks at all aspects of the operation, but with an especially with a keen eye on HVAC controls. A facility can have state-of-the-art mechanical equipment, but if the controls are not set up correctly, even the most advanced system will function poorly. In many cases, a new owner or occupant moves into a facility and brings a different business plan than the one originally designed for with the facility.
For example, a technical facility used outside air that was being introduced at high levels at all times of the day, as originally set up. The current occupant, however, operated on standard business hours, not around the clock. By changing the sequence of operations in the facility to match the occupant's business schedule, the owner saved $8,000 per month in energy costs.
Or consider the example of a public facility with multiple uses and schedules. The organization spent money on lavish architecture and interiors but omitted commissioning, testing and balancing in favor of initial cost savings.
Once the facility began operation, mechanical HVAC issues created frustrating operation problems, including thermal comfort, pressurization, and high energy costs. The owner can resort to retrocommissioning in such cases, but the money to address all of these problems most likely would have been enough to pay for the commissioning, test and balance for the facility in the beginning.