Pipes Making a Knocking Noise? Call Us For Easy Fix 24 Hours

pipes-making-a-knocking-noiseIf you have a steam boiler in your home, you might notice at some point that the pipes are shaking, rattling, or otherwise making loud banging noises. This isn’t all that uncommon for steam boilers, but it’s actually not normal at all.

Although no plumbing or heating system is completely silent, pipes making a knocking noise isn’t something that’s actually supposed to happen.

If your steam boiler pipes are emitting a noisy cacophony, there are actually several different reasons for pipes making a knocking noise. The cause of a noisy steam boiler pipe could be a maintenance issue, or an installation and design issue. Here are some of the top reasons for banging noises coming from noisy steam boiler pipes:

  • Improper pitching. Steam boiler pipes can become noisy if they’re not pitched correctly. The pipes are supposed to be installed so that they slop downward, moving water and steam via the force of gravity.

If the steam pipes are bent or sagging, it will obstruct the normal flow, resulting in noisy, banging sounds. In many cases, a kink in the lines occurs because one of the pipe hangers has broken, creating an area where condensate will pool up. Eventually, it gets the point where it does come out, all at once, hitting the end of the line loudly.

  • The pressure of the steam is too high. If your pipes are making a knocking noise, it could also be because the pressure inside is higher than it should be. The pressure inside your steam boiler pipes isn’t meant to exceed about 2 psi.

If it does, it can start to back up into the return line, causing the pipes to begin knocking periodically. This can be fixed by adjusting the pressure settings.

  • Clogged condensate lines. Knocking or banging steam pipes can also result from an obstruction in the condensate lines. This is most likely to result from accumulated rust, especially in older steam boilers. For this issue, you’ll probably need a professional steam boiler pipe repair service.
  • Failed steam traps. Loud banging noises from your steam pipes can also occur because the steam traps are failing. This allows steam to move into the condensate return lines, where it pushes the water along. The water hits the sides of the pipes, causing knocking or banging sounds.
  • Poor steam pipe insulation. Insufficient insulation is another common cause of noisy steam boiler pipes. If they’re not fully insulated, the steam will begin to condense along the sides, causing a banging or hammering sound that emanates from the steam pipes.

Fortunately, you don’t have to put up with noisy steam pipes and knocking sounds forever.

At Degrace Plumbing, our experienced contractors can easily diagnose the exact reason for your noisy steam boiler pipes, so that we can perform the appropriate repairs.

We routinely work with steam boilers from dozens of top brands, including Weil-McLainUS Boiler CompanyLattner, and more. To find out more about steam boiler pipe repair in New Jersey, call us today at 201-997-8565.


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