Noisy Water Heaters: The Causes And What You Can Do To Fix It

Water heaters, much like pipes, can be pretty noisy. Most people tend to think nothing of the noise and simply choose to ignore it. But you do not have to, there are plenty of reasons why your water heater may be noisy, some of which can be fixed relatively easily. We did an earlier post on how homeowners could deal with noisy pipes, so it seemed like a good idea to do one on how to deal with noisy water heaters.

Identifying the noise

The first step when it comes to dealing with a noisy water heater, is to identify the noise that the water heater actually makes, as the noise the water heater makes is pretty indicative of the problem that is plaguing the water heater. Is it a humming noise, a rumbling noise, a banging, it is crucial that you correctly identify the noise made by the water heater. When you are talking with a plumber, being able to describe what sort of noise the water heater makes will help the plumber identify the problem quicker.

Causes

Sediment buildup

By far and away the most common cause of noisy water heaters is the buildup of sediment in the water heater. Sediment is a naturally occurring material that can be found in water. All water heaters suffer from sediment buildup. The sediment will settle at the bottom of the water heater, and gradually form a complete layer of sediment. So, why does sediment cause noises exactly? Well, as the sediment settles on the bottom of the water heater, gaps are left. The water gets in these gaps and settles. As the water heater heats up, the water in these gaps also gets heated up. The heated water interacts with the sediment, which then causes a popping noise (the popping is the sound of the sediment being broken apart). So, if you hear an odd popping noise in your water heater, then you know that it is because sediment is being broken apart.

Of course, the broken sediment does not go away. If there are a lot of pieces of broken sediment within your water heater, then those pieces will get swirled around by the water heater, and cause a “banging” noise as the sediment hits the inside of the water heater.

In both cases the solution depends on how long the sediment has been in the water heater and how much sediment there is. The way to avoid excessive sediment buildup is by regularly flushing your water heater. Flushing is a rather simple process, simply turn off your water heater, and then turn on a hot water faucet somewhere in your house (this prevents a vacuum from being formed). Attach a long hose to the water heater’s drain valve (if you do not know where that is, it is located somewhere near the bottom of the water heater) and run the hose outside. Open the drain valve and let the water flow out. Pay attention to the colour of the water; murky water means that the water is full of sediment, which is good, since you want the sediment to be drained out of the water heater. When the water is clear, then you can stop the flushing, as that means that most of the sediment has been removed from the water heater. Doing this regularly will prevent sediment from damaging your water heater or causing loud noises. If there is too much sediment in your water heater, then, in addition to loud noises, your water heater’s steel and glass lining will begin to weaken, which leads to the water heater breaking.

Water hammers

“Water hammers” refers to the sounds made when water going through a pipe is suddenly stopped, which causes a large banging noise. Now, water heaters do not cause water hammers, so, you to solve this issue you do not actually have to do anything to your water heater. If you are hearing a large banging noise whenever your water heater is in use, it probably just means the water hammer is occurring close to the water heater. The solution is rather simple, call a plumber and get a “water hammer arrestor” installed in the section where the water hammer occurs.

Loose parts

If you hear a humming noise when the water heater is in use, then it is usually a sign of loose parts. When the water is in motion, it causes the loose parts to vibrate, which causes a noise. For example, in many electric water heaters, the heating element is located on the side of the water heater. If this element is loose at all, then a noise will be emitted when the water heater is in use. There is no danger, but if the noise really does annoy you, you can quickly tighten the loose parts.

Heat traps

Water heaters come equipped with heat traps to prevent the loss of heat and keep the water at a certain temperature. As water flows through the water heater, these heat traps can expand and contract, which can cause a faint noise that is best described as a “tapping noise.” There is no real solution here, other than getting new heat traps installed, but that is obviously going to be an expensive solution for a rather minor problem, so it is probably just best to live with the noise. If you do want to get heat traps replaced, call a plumber or someone licenced to work with water heaters and have them install new heat traps.

Just because your water heater is making some strange noises does not mean you have to panic and immediately call the plumber, but at the same time, you should not just ignore the noises either. Water heaters are never going to be quiet, but they do not have to be excessively noisy either. So, if your water heater is making noises, do not immediately drop everything and scramble for a plumber, but do make sure to get the issue checked out by a licenced plumber.