The Evolution of Steam Trap Monitoring for ESCOs in the ESPC Marketplace

Steam traps are an integral part of the steam condensate removal system.  Steam traps are often the lead indicator of the overall system health and, when properly maintained, can generate immediate fuel savings with an ROI that cashflows inside of the standard 15-year ESPC term.  Most ESPC projects include some form of steam trap testing, repair and replacement where steam is present. 

Many ESCOs like to remove and replace the entire steam trap population to standardize on a single manufacturer.  Because the ESPC service term is often as long as 15 years, establishing a baseline can facilitate annual maintenance, thereby improving the likelihood of meeting the savings guarantee.  This maintenance is typically included as part of a yearly steam trap testing program.  Generally, the ESCO is right to pursue this path. 

Why?  Because the steam trap population is old, often, many of the traps are beyond their useful life span.  It is not uncommon to find several different makes and models of steam traps in service, some being obsolete with limited options for repair parts.  There are also occurrences where steam traps are not installed as intended, installed without isolation valves and strainers with blowdown valves, or are misapplied for the equipment they service.  Still, sometimes test and repair programs are all that is needed or that can cashflow a project.

Steam traps also happen to be installed in some very inconvenient places. They can be found in crawl spaces, steam vaults, inside walls, in every classroom, patient room, closet, office, and hallway. They also lurk in or on ceilings mounted 40 feet in the air or the farthest corner of a penthouse attic space.  All this contributes to making maintenance of the entire population very difficult and is why this is a service most facilities prefer to outsource.

Additionally, steam traps generally are controlled by valves that operate to meet demand, which contributes to the difficulty of testing traps to determine failures.  Testing the steam trap means you must be prepared to bypass the control valve either with a partner at the BMS terminal or by overriding the pneumatics.

Steam traps fail. Many steam traps have a float and/or thermostatic bellows that fail over time.  They also have gaskets that tear or wear out. Depending on run hours, quality of steam, system pressure, and debris in the system, traps can begin to fail within three years of service. This is why mud-legs, strainers, and blowdown valves are so important to have in place and maintained.  

WHAT DOES ALL THIS MEAN? 

Traps can be operating correctly one day, maybe the day that they are tested, assuming they are tested, but then fail shortly after testing. So what is the best practice solution to all this potential steam loss?

Steam Trap Monitoring

Steam trap monitoring is not as easy as it sounds, or as hard as it used to be.  Traditional and legacy monitoring systems may require utility interruption, a steamfitter to install and can cost as much as  $2,000 per trap when factoring in gateways, conduit, and wiring, monitors, labor, setup, and maintenance.

Also, there are many types of steam traps, each has a unique function and is designed to operate on continuous or modulating loads, at different operating pressures, and to handle a wide variety of condensate loads and temperatures.  Each trap needs to be explicitly programmed into the monitoring system so that the monitor is capturing data that corresponds to the operating condition and functionality of the trap.

Another problem with most legacy monitoring systems is that the data has to travel through the IT firewall before the monitoring dashboard, introducing network security concerns.  The monitoring system owner must consider that the network administrator is changing passwords every three months on average, which means a quarterly reset of the system is required to keep it reporting. 

The good news is that technology advances in this sector have created the ability to monitor the high run-hour, high capacity, and critical equipment steam traps.  When strategically deployed in coordination with a steam trap testing program for the balance of traps, these systems can be installed at a very reasonable price and cashflow in the ESPC program.

The added benefit to M&V engineers is the ability to predictably manage savings. 

Costs for next-gen systems can be as low as $600 per trap, and utility interruptions are no longer required. The improved technology, usability, and affordability is all good news for the ESCO project development engineer looking for a better way to upgrade and maintain the steam trap population for their very important customer.

Contact me for more on this topic at jmoore@steammgt.com.

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