Why is my boiler making a humming noise?

You probably cannot count on boilers to be in the list of quietest heating appliances so far, but some sounds from your system can ensure you on the existence of a problem in your unit and that is when you need to learn on why your boiler is making noise when heating is on. One of those noises can be a loud humming noise which is not a normal boiler sound produced during the operation of a healthy boiler.

This humming sound cannot be pleasing and would require you to figure out the issue and solve it as soon as possible. So in order to answer your question as to why is my boiler making a humming noise, we have mentioned a few points below.

From our understanding of boilers there can be 3 main problems that happen to be the reasons of your system making a humming noise.

1)    Loose components:

One of the most common reasons of your boiler making a humming noise while operating could be any of the components of your system might have made its way to loose. A component when silently vibrates against the other parts, produces a loud humming sound that needs to be fixed. Though the fix is simple, yet delaying the repair could cause your boiler to get even more damaged. Once you are sure about the issue, stat looking for :

1. Loose brackets- You can try fixing the loosen bracket area with a screw or screwdriver.
2. Vibration of the unit itself- It is highly recommended to go for a professional help in case you find your system to be vibrating in order to stop the unit from making certain noise.
3. Open panel/compartments- An open panel or compartment in the system can also be a cause of the sound being produced. While for this, you need to make sure that all the compartments, panels, and openings are well closed.

2)    High pressure:

• If your boiler is making a really loud humming noise then you need to look out for the water pressure of your system. A system operating on a higher pressure can be a cause, contributing to the loud sound that is being produced.
• A considerable point in this case is that a normal healthy boiler would never exceed the pressure limit of 12-15 psi (pounds per square inch). So if your boiler is operating at a pressure over 15 psi then this could be the reason for your system to produce that sound.
• Although, this is not felt to be like an emergency case, as the modern systems are made with the pressure relief valves to handle such problems for you. But if the problem continues for a longer time then you could try turning the water and heating off, which is believed to help you put the pressure back to the normal levels. For other high pressure issues it is highly recommended to consider a professional help.

3)    Circulating pump set too fast:

• The circulating pump operates to circulate the heated water from the boiler to radiator and then back to the boiler. If the circulating pump somehow gets set at a faster speed, then you would witness vibrations and a loud humming noise.
• If that is the case then you need to look for the circulating pump of your system, and check the speed settings. Reduce the speed of the system and see if that stops the humming noise.
• If the sound stops, then leave your system to operate at a lower speed but if this doesn’t solves the problem or causes any hot water discomfort to your family then you are highly recommended to consider a professional help in that case.

While on a clear note these are not the only issues that cause a humming sound in your boiler but these are some of the most common reasons that happen to disturb your peace of mind.