Building Automation: Why Is It That Control Systems Don't Work?
We recently had a chance to catch up with an industry acquaintance and were describing some of the energy efficiency programs we were designing. Imagine our surprise when he responded with this question, “Why is it that it seems like control systems in commercial buildings never work?”
At first, we were taken aback by the question. After all, we see controls and BAS as being a key element to the delivery of a sustainable, high-performance building. Unfortunately, we quickly realized that he was right. In evaluating existing buildings from new to vintage, we almost always find partial to complete failure of control systems.
Why does this happen, and more importantly, why do we think that it is possible to have systems that work? Our observation is that the failure of these systems has little to do with the availability of quality controllers or sensors, but has to do completely with the process involved in designing, building, and running these systems. To elaborate, the root causes are as follows.
DESIGNMany control systems fail in the design phase. Often, design engineers may view controls and BAS as an afterthought, with little detail being put into designs. Perhaps it is easier to just modify a vendor’s guide spec or to re-use an existing document with minor updates. The biggest problem we see is in the details. What exactly are the required sequences? How will the systems be optimized? What exactly should the user interface look like? What points are required?
A well thought-out, detailed, and appropriate design is the key to a successful system. How this is accomplished may be a good topic for several future columns, but it likely involves training, a strong systems focus, and the appropriate changes to fees and schedules.
INSTALLATIONThere are some excellent controls contractors and system integrators in practice today. The challenge is to find these suppliers and to work closely with them to make sure that systems get properly detailed, documented, installed, programmed, and commissioned. Working closely with good contractors can give great results.
Unfortunately, the corollary to this is also true, resulting in poorly installed, tested, and documented systems. Of course, even a great control solution won’t work with a poorly designed or installed mechanical system. Attention to proper installation and commissioning is critical for high-performance operation.
OPERATIONSOnce the project is completed, it falls to building operations to make it work properly throughout the lifespan of the building. Providing building operators with the right processes, focus, tools, and training can result in a platform for sustained efficiency. Even a great operator isn’t going to be able to get a control system that has been improperly designed or installed to work though.
The answer to our acquaintance’s question is that control systems can work well and that should be an expectation for any project. Focus on thorough control design and installation, coupled with good training and tools for continuous commissioning and monitoring. These are the keys to the delivery a high-performance building operation platforms. ES