The term “belt-tightening” refers to an intended decrease in spending. But when applied to an HVAC preventative maintenance program, it can literally mean the difference between a simple, inexpensive fix and a potentially costly capital equipment misdiagnosis.
Any complex system, and the equipment that runs it, requires preventative maintenance — just like your car. Proper care through regular upkeep keeps things running smoothly for years and can help with energy savings.
HVAC systems in commercial buildings experience performance degradation over time. Frequent operational and occupancy changes can push systems to their limits, resulting in less than stellar operation. Retro-commissioning uncovers the problems.
Performance testing during the retro-commissioning process compares system operational efficiency to its original design, as well as current facility requirements. Evaluations can identify opportunities for improvement for common problems, such as lower than desired airflows.
While engineers can be quick to assume that this sort of problem is related to past ductwork modifications, they often recommend new or additional equipment.
The following example highlights the difference a simple repair can make.
The Right Diagnosis
A recent retro-commissioning project completed by Edison Energy’s Engineering Solutions team required testing an area with many occupant comfort complaints. Sure enough, we recorded airflows that were 60 percent of design.
The initial diagnosis was to replace the fan, or provide an extra fan to help improve airflow. But a simple visual inspection, along with an audible squeal, revealed worn-out drive belts.
It wasn’t surprising to learn the facility lacked a preventative maintenance program. The belts had never been inspected since the system was installed. Had preventative maintenance been in place, the belts would have been replaced and likely mitigated comfort complaints sooner.
Test data revealed a stark difference in performance after the repair, with a large increase in airflow, static pressure and fan speed.
While energy usage in this case will increase, the comfort complaints will be resolved — and importantly, the facility did not need to install new equipment.
So, what’s the lesson? Before thinking there’s an expensive problem, check the equipment first. Better yet, set up a preventative maintenance program.