Why is My Water Heater Making Noise?

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

Here’s what to know about the noises your hot water tank is making from your friends at 1 Call Plumbing


Popping Noises
The most frequently reported hot water tank noise can be described as a “popping” or “rumbling.” It’s noticeable because it’s often pretty loud, and it definitely registers with most people as unusual.

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

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

Humming Noises

Some noise from your 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 you can do: Tighten the heating element slightly (don’t overtighten!) to prevent vibrations, or have a plumbing professional do it for you.

Knocking Noises
Are knocking noises coming not from your water heater, but the walls in and around the heater? If so, you’re probably hearing 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 your studs or even your sheetrock, as well as to the plumbing elements.

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


1 Call Plumbing gets calls all the time from people concerned about noises coming from their water heater. For the most part, noises aren’t cause for alarm unless they’re extremely loud or very sudden. Either way, your hot water tank should be inspected by a licensed plumber to make sure there’s nothing serious going on.

Need help with your heater? Give the 1 Call Plumbing team a call anytime for a hot water heater inspection.