Why Is the Water Heater Making Noise?

Water heaters are a common source of plumbing issues because, whether traditional gas or electric, they are just giant tanks filled with water! One of the first signs of trouble with a water heater can be a noise, specifically popping, banging, and creaking noises. What do they mean, and should a homeowner worry?

Here’s what to know about the noises a hot water tank is making.

Popping Noises

Plumbers report that the most frequent hot water tank noise can be described as a “popping” or “rumbling.” It’s noticeable because it’s often loud and definitely registers with most people as unusual.

What it means: These noises mean the water heater is succumbing to sediment build-up at the bottom of the tank. Sediment—or scale—build-up can wreak havoc on the tank over time, dropping its efficiency and even causing it to spring a leak which probably necessitates a replacement.

What to do: Contact a professional plumber for help draining and flushing the hot water tank. It’s a relatively straightforward process and doesn’t usually require many special tools, but it can be tricky, mainly if the water heater is hard to reach.

Humming Noises

Some noise from a hot water tank is normal, like humming. As long as it’s not very loud or sudden, a humming noise isn’t usually anything to worry about long-term.

What it means: Water flowing around the heating element inside the tank is causing vibrations, releasing a humming sound from the tank.

What to do: Tighten the heating element slightly (don’t overtighten!) to prevent vibrations, or have a plumbing professional do it.

Knocking Noises

Are knocking noises coming from the water heater or the walls in and around the heater? If the sound is in the walls, it’s likely the sound of pipes banging against each other inside the walls as water moves through them.

What it means: Water has been abruptly arrested from coming or going to the tank, causing a jerking motion in the plumbing pipes situated within the walls. Over time, the motion can cause damage to the studs or even sheetrock, as well as the plumbing elements.

What to do: Have a plumber perform some tests to determine which pipes are creating the knocking. From there, a licensed plumber can install a water hammer arrestor to better regulate the flow of water in and out of the heater.

When in doubt, homeowners should contact a professional plumber to inspect their water heater. Should there be a problem, the plumber can suggest appropriate repairs or advise on the best replacement option.

Royalty Plumbing offers high-quality residential plumbing services in the areas of Las Vegas, Henderson, North Las Vegas, and Summerlin.