Is a Water Heater Whistling Dangerous?

Water heaters seem to be the way of the world these days, providing fast, convenient hot water wherever you need it. As all machines do, they may begin to have some problems over time. Today, we’ll take a look at what it means when your water heater starts to whistle and what to do about it. Ready? Let’s dive in.

It’s a cold winter morning, and you walk past your water heater, a cup of coffee in hand. As you pass by, your water heater begins to whistle. Annoyed, you go turn on the tap to check for hot water and are surprised to find it still in working order. So now what? If the hot water heater is still working, should you worry about the noise it’s making?

Let’s take a look.

How Does A Hot Water Heater Work?

To better understand why your hot water heater is whistling and what to do about it, the best way to begin is with how the unit works. The unit consists of a water heater tank, with a heating mechanism at the bottom too, you guessed it, heat the water. At the top of the tank is a dip tube where water flows into the tank, otherwise known as a cold water inlet.

As the water enters the tank, it drops to the bottom and is heated by the mechanism located at the bottom of the water heater tank. As it warms to the desired temperature, it floats to the top and leaves the tank through the heat out of the pipe, otherwise known as the hot water outlet (excessively clever, we know).

Now that you understand the basics of how a hot water heater works let’s diagnose that whistle (it’s even worse than your whistling).

Why Is My Water Heater Making A High-Pitched Sound?

A standard water heater should not make high-pitched sounds, if any at all. However, there are several different things that cause the excess noise.

Leaking & Cracks

In the realm of noises coming from a water heater, a light sizzling is often a result of leaks or cracks somewhere with the water heater. This can often be difficult to get to the bottom of, and we recommend calling a professional for assistance.

Sediment Build-Up

Sediment build-up is very common in water heaters, resulting from poor maintenance of the water heater tank over the years. The sediment builds up on the bottom of the tank, causing a high-pitched noise any time the heater is turned on. Maintenance flushes of the water tank help prevent this problem.

High Temperature & Pressure

If your water heater is experiencing excessively high temperature and pressure, this is likely because of the TPR valve. The TPR valve, or temperature pressure relief valve, is in charge of relieving pressure. When constant whistling occurs, the TPR valve may be having trouble releasing the amount of pressure necessary to keep it from reaching dangerous levels.

What To Do If The Water Heater Is Whistling?

When you begin to hear whistling, turn the tank completely off before you begin to troubleshoot. If you determine, the whistling has something to do with the sediments built up in the tank, a quick flush will do the trick.

If no sediments are built up in the tank, there are a couple of other things to check for. Again, be sure the tank is turned off and has had time to cool down before looking for signs of malfunction. If there is any water or moisture collected underneath the tank, you more than likely have developed a leak in the water heater and should give a plumber a ring (we mean a call, not an engagement ring).

Is My Water Heater Whistling Dangerous?

Yes, if your hot water heater is whistling, there is a good chance it is dangerous. As a water heater is not supposed to whistle, it should be considered a warning, and you should act to correct the issue as soon as possible.

As we mentioned before, a whistling sound can be a sign of failure in the TPR valve. The TPR valve functioning correctly is absolutely necessary for a water heater to run properly. Built-up pressure with no safe release is extremely dangerous and has previously caused water heaters explosions.

We can’t say it enough. If you notice a whistling sound in your hot water heater, turn it off immediately and contact a professional.

Carbon Monoxide Poisoning

While it is unlikely, it is not unheard of for malfunctioning water heaters to cause carbon monoxide poisoning. This can be due to cracks, leaks, or whistling in the water heater. Because carbon monoxide is colorless and does not have a distinct scent, it can go unnoticed.

A general rule of thumb is to have a carbon monoxide detector near your water heater to detect malfunctions in your heater, even if you don’t notice them.

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