Just How Automated is Your Building Automation System?
To keep your building automation system operating at peak performance, you might have to work a little harder than you thought.
Building automation systems (BAS) can help save energy and improve indoor comfort, but not everything is automatic. Although a BAS does automate many sequences of operation of building system equipment, optimizing performance still requires some human intervention.
The following are a number of factors that can impact BAS performance. They might leave you wondering if your BAS is truly automated.
Human error, faulty judgment, lack of training and fatigue can all affect BAS operation. Building occupants open windows and cover vents. Maintenance personnel may unintentionally permanently suspend or change sequences and set points that were meant to be temporary. Staff may allow the system to operate in fail-safe mode for too long. Reliance on automation can also decrease the use of valuable human senses, such as smell, hearing and touch.
Just because a system is automated doesn't mean everything is correct. An HVAC process may be poorly written. Control software naming conventions can be confusing. Poorly documented code can result in operators overriding the sequence of operations because they don't understand it. Also, sequences might be wrong or inadequate from the start. Commissioning can be a helpful tool in clearing up these types of issues.
Building systems contain many components that can affect BAS performance. An undersized motor or the use of a failed open valve can result in incorrect operation. Cybersecurity can be compromised. Neglected components u2014 such as economizers and humidifiers u2014 may stop operating correctly. Replacing a controller with another brand may limit its interoperability in the network.
Equipment degradation and clogged filters can result in performance drift. Filters may not match the available pressure differential. Upgrading from a MERV 8 to 13 filter or HEPA filter can restrict airflow too much. Adding polarized refrigerant oil might clog the heat exchangers.
Sensors and controls are critical to BAS performance, but they can create serious issues if they're not functioning correctly. Poorly calibrated, non-functioning or poorly located sensors can degrade performance. Setting every alarm to the same priority can be overwhelming to a human operator. A spurious signal might come from an aged sensor. Dampers may leak because they don't completely close or open even though they are commanded to do so.
Seasons change. The BAS might overcompensate for abnormal environmental events like extreme temperatures, dust storms or smog. The interaction of temperature, humidity and airflow rate is complex and is different for inside rooms, compared to rooms with walls that are part of the exterior building envelope.
So, your BAS requires regular care to keep operating at peak performance. You'll still save plenty of time and money, but you might just have to work a little harder than you thought.