Commercial boiler systems are working hard this winter, having to warm apartment buildings, offices, retail spaces, and more. But, if your system is struggling to heat your space and tenants are beginning to complain, you may have a buildup of sludge in your system. Here are some insight and advice from NJ commercial HVAC contractors.

What is Sludge?

This is a common term for magnetite, which consists of a thick black substance that is mostly composed of dissolved and rusted metal from the piping and tanks of commercial boiler systems. It forms when the water in the system reacts with air and ferrous components (like steel) and, because it is heavier than the water in the system, it sinks down and settles in the bottom of the radiators, pipes, and tanks.

What Is the Effect of Sludge Buildup?

Corrosion is never a good thing for commercial heating systems, and over time, sludge buildup can lead to:

  • Poor radiator performance (it will feel hot at the top but cooler at the bottom),
  • A more frequent need for radiator bleeding,
  • Hot pipes but cool radiators,
  • Leaking or failure of the boiler pump,
  • Increased commercial boiler system repairs (parts wear more quickly due to strain and corrosive debris),
  • Noise complaints about the heating system (gurgling and rattling noises are common), and 
  • Increased energy bills as the heating system has to work harder to deliver the required heating.

Over the long term, sludge can restrict the flow of water through the system’s piping, which can be labor-intensive and costly to repair if it blocks pipes near the heat exchanger. Blocked boilers can overheat and shut down, and damage to the boiler, pumps, radiators, pipework, and heating system components can be expected if sludge is allowed to build up.

How to Prevent a Sludge Buildup in Commercial Boiler Systems

Fortunately, there are solutions to the dreaded black sludge issue. Firstly, it is essential to have your commercial boiler system serviced on an annual basis. Any commercial boiler system can start to corrode (although older systems are more likely to experience this issue), and it is vital to correct it as soon as possible to prevent costly damage and heating system downtime.

Your commercial HVAC company can also recommend preventative measures, which include:

Chemical Inhibitors: These disrupt the corrosion process that forms the magnetite, preventing the development of black sludge. It’s not a complete solution, however, as it simply slows this process down dramatically, which prolongs the lifespan of your commercial boiler system. This inhibitor will have to be introduced into the system at regular intervals.

24/7 Repair Services in New Jersey for Commercial Boiler Systems

Tri-Tech Energy is an established commercial HVAC and commercial heating systems company in New Jersey with a reputation for professionalism, expertise, and competency. We’ve been working on commercial and industrial projects, including commercial boiler systems, for decades. For more information on our company or services, which also include commercial boiler service programs, repair, and maintenance, please contact us today and speak to a qualified commercial HVAC contractor or visit our website at