Why Is My Boiler Making Banging Noises?

Covering ears

Posted: March 14, 2019

A noisy boiler can be a fairly common problem for people who have a closed loop hot water boiler. Similar to a radiator in your car, your boiler is filled with water. But if air leaks into the system, the pressure rushes through the pipes. This results in a banging noise.

Why does this happen? Air can be drawn into the system in several different ways. This includes a defective valve, a broken bleed screw, a pressure leak, or previous repairs done to piping.

Another possibility is a problem with the expansion tank. Because water expands when heated and contracts when cooled, extra space is needed to store air. This is called an expansion tank. But air can be drawn back into the boiler from this device.

Noises from your burner

Of course, banging sounds are not limited to boilers. An oil burner with a partially blocked nozzle can exhibit some outward signs that you should be aware of. You may notice an odor because fuel is dripping out of the nozzle after shutoff, which would result in unburned fuel in the combustion chamber.

When the system fires up, this would cause a small boom, bang or rumble, which needs to be addressed. Dirt on the burners delay the burners from igniting, causing excess fuel to build up. So when the fuel does finally ignite, you’ll hear a loud bang. You should never ignore this noise because these small bangs could strain your system, and eventually result in a breakdown.

As you can see, there are a variety of things that can go wrong, and even if the noise is minor right now, that doesn’t mean you shouldn’t get it checked out.

To prevent costly problems, contact us so we can do a professional inspection of your heating system.