Today’s automobiles have become an integral part of our lives. We depend on them to perform. We expect them to be comfortable, and because of the high cost of fuel, operate efficiently. Most of us don’t think twice about “tuning-up” our cars after several years of use. We do it knowing that it will improve the performance.
The procedure is simple. We call our trusted service mechanic to check-out our car using the latest in high tech testing equipment. Many see the “tune-up” as a regular maintenance function, and usually associate it with the replacement or adjustment of components in the mechanical, electrical and fluid systems. It isn't a cure all, but when done regularly and by an expert, it can revitalize our vehicle, making it more comfortable, run efficiently and prevent a host of expensive problems down the road.
Today’s modern building isn't any different. Maintaining performance means a regular “tune-up”. Without exception after it's first year or so, the systems begin to slide down the performance curve and efficiency diminish. As equipment ages it naturally deteriorates, controls get overridden by maintenance staff trying to solve a symptom, or change operational and occupancy parameters from which initial programming was based.
A building tune-up or Re-Commissioning, as its known, is predominantly a hands on process that tests the functionality of an existing building and compares it's current operating efficiency with another benchmark building of the same type and use.
Usually with the help of the buildings automation system the commissioners will test the HVAC, lighting and water systems to find out if equipment needs to be adjusted, replaced or re-calibrated to an optimal performance level. This provide comfort for the occupants and reduces cost of operation. A side benefit to any adjustments is that it often uncovers and corrects many energy wasting issues and in some cases identifies a potentially costly failure.
Lawrence Berkeley Laboratory concluded in extensive studies that “recommissioning is a cost effective means to “tuning up” to provide energy efficiency in a facility. It has proven to be an inexpensive first step to improving performance and cutting energy costs. In most cases it will provide the owner a return on investment in less than a year.
Some of the most common measures found in re-commissioned facilities include:.
1. Adjust control sequences of operation.
2. Reduce HVAC equipment operating hours.
3. Readjust zone temperature dead-bands and set-points.
4. Re-balance HVAC air and water systems.
5. Adjust and repair economizer dampers and controls.
6. Re-condition or balance chilled water and hot water systems.
7. Adjust and repair or replace lighting and occupancy sensors, controls or schedules.
8. Replace older fluorescent with energy efficient lighting.
9. Reduce supply duct static and water pressures.
10. Implement demand response strategies.
Once issues are uncovered and the repairs are implemented. The follow up is training of the maintenance staff, and tracking of performance using the trend data. It is recommended that a pre and post energy benchmark is established using this stored data to monitor and verify continued performance.