Why New Isn't Always Better: The Case for Re-Commissioning

In today’s world of rapidly evolving technologies, it’s easy to assume the newest solution is the best one. Building Automation Systems (BAS) are no exception. Often, features marketed as “new” and “advanced” are simply repackaged iterations of existing functionalities that users may not realize they already possess.

The core of any BAS remains the same: a network of binary and analog inputs and outputs. What is constantly changing is how you can arrive at the same performance outcomes based on different algorithms or new complex programming. So, when faced with persistent building performance issues, should you upgrade, replace, or consider an often-overlooked third option—re-commissioning?

It is important to note that building owners have already invested hundreds of thousands, if not millions, into their current BAS systems. Many leading controls companies, such as Johnson Controls, Siemens, and Trane, design their newer products to be backward compatible, eliminating the need for hardware upgrades. While upgrading your Building Management System (BMS) can result in energy savings, true efficiency gains don’t come from replacing field controllers, servers, databases, or graphics. The key to energy efficiency lies in updating control strategies to more modern, efficient methods and recommissioning the inputs, outputs, and algorithms.  

The Case for Re-Commissioning

There are many reasons that building owners lean towards replacement or upgrades when so many problems in the building persist. With the endless demands of building operations, a complete system swap can seem like the simplest solution. However, a sledgehammer approach often isn’t necessary. What’s often needed is the precision cut of a scalpel.  

Issues can snowball. A single minor issue downstream in a system can quickly move upstream and cause inefficiencies without effort. For example, a single uncalibrated terminal unit airflow station serving a single room. While it might seem like a small inconvenience, the consequences ripple throughout the system, affecting efficiency and increasing energy costs.  

Consider the common issue of a miscalibrated or damaged Variable Volume Boxes and their impact on your energy consumption.  

• When VAVs are over-delivering air to a space, this requires the associated air handler to increase its fan speed.
• This pushes more warm air across its cooling coil, thus opening the valve more to remove the load being delivered to the AHU.  
• This requires the associated air handler to increase its fan speed, which in turn pushes more warm air across its cooling coil, thus opening the valve more to remove the load being delivered to the AHU.  
• When the AHU cooling coil water picks up the heat load from the air, it puts additional demand on the chiller which removes the heat from the return water of the AHU.  
• Lastly, as the chiller loads up for more cooling demand, the cooling tower then has to dissipate the heat from the condenser water of the chiller.  

This chain reaction illustrates the long reaching effects of something as simple as a VAV Box not working properly.

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Identifying and Correcting Performance Issues

Let’s examine three VAV boxes in operation:

• VAV-1 is over cooling. You can see that the damper is open when it should be closing off to reduce the amount of air being delivered. Perhaps the damper linkage has become loose.  
• VAV-2 is operating normally.
• VAV-3 is not heating the space. This could be a stuck closed heating valve.

By re-commissioning the system you can calibrate sensors, verify mounted devices, test sequences of operation and avoid such instances from occurring.

Re-Commissioning: Applying the Scalpel

With precision planning and identification of source issues, entire systems can be repaired with new software/algorithms applied, leaving existing sensors and hardware in place.  

Here are some basic control strategies that can be implemented with your current BAS System without the need for costly replacement. These are all software driven tasks:

• ‍Occupancy schedules with morning warmup and cooldown cycles
• ‍Supply air temperature and/or pressure reset for air handling units
• ‍Chilled water temperature resets on chillers
• ‍Economizer mode for enhanced cooling
• ‍Optimal start/stop algorithms to prevent unnecessary run times

The 6 Biggest results of Re-Commissioning

1. ‍Improve energy efficiency: Re-commissioning can help buildings run more efficiently, which can lead to energy savings of 8%–22%.  
2. ‍Reduce operating costs: Re-commissioning can help reduce the amount of energy consumed by a building, which can lower operating costs.  
3. ‍Improve indoor environment: Re-commissioning can help improve indoor air quality, temperature control, and noise levels.  
4. ‍Increase tenant satisfaction: Re-commissioning can help make occupants more comfortable and satisfied, which can lead to increased productivity.  
5. ‍Reduce unexpected repairs: Re-commissioning can help identify and address issues before they lead to unexpected repairs or replacements.  
6. ‍Ensure maintenance personnel are trained: Re-commissioning can help verify that maintenance personnel are trained and have the documentation to operate the building efficiently.

Ready to unlock the hidden potential in your existing BAS?

Let’s talk about how re-commissioning can improve performance, cut costs, and extend the life of your systems without a full replacement.

Connect with a BranchPattern Expert today to schedule a consultation.