What Do the Noises Coming From My Water Heater Mean?

Technician servicing an hot-wWater heater

It’s common for water heaters to make noises at some point in their lifetime. But not all noises are a cause for concern. The types of noises that can come from your water heater can vary from hissing and rumbling to rattling and popping sounds. In this blog, you’ll learn what these sounds mean and what you can do about them!

Common Causes of Water Heater Noises

Sediment Buildup

Over time, sediments and minerals can build up inside your water heater. When this happens, it’s common for water heaters to make a popping sound. This sound is caused by water bubbles passing through the sediment layer. Though this issue isn’t necessarily dangerous, it will eventually weaken your water heater if left unresolved, causing it to overheat.

Loose/Faulty Parts

Old, loose, or otherwise faulty parts of your water heater can cause humming, hissing, or rumbling noises. For instance, water heaters tend to have heating elements on both the top and bottom. When cold water enters the tank, these parts can shake, causing humming noises. If you hear these noises, you may have a faulty part on your water heater, or you need to tighten the heating element.

Water Flow/Pressure Issues

Sizzling is another common noise that can come from your water heater. This sound usually indicates that there may be an issue with your water flow. This is because water isn’t easily flowing into the tank. Infrequent pressure levels can cause hammering sounds. If this is the case, it may not be stemming from your water heater at all but from water pressure outside your home. This can cause serious damage to your water heater if not taken care of immediately.


Apart from water flow issues, leaks and/or condensation can also be causes of hissing noises. Naturally, your water heater can become extremely hot as it heats your water, so when there is a leak, that water can come in contact with highly heated parts, creating a sizzling noise. When trying to figure out if your water heater does have a leak, search for puddles near or around it.

Troubleshooting Tips

If you’re experiencing one or all of these odd noises coming from your water heater, you can try a few of these steps to fix the problem.

  • Tighten loose parts – Loose parts can rattle around as cold water enters and moves around within your water heater.
  • Flush out your water heater – This eliminates any buildup that may have accrued in your water heater.
  • Install a water softener – A water softener helps prevent sediment and mineral buildup.
  • Ensure pressure valves are open – Opening pressure valves will improve your water flow, minimizing hissing sounds.

No Luck? Call in a Professional

Noisy water heaters can be frustrating and cause unnecessary amounts of worrying. If you still hear hissing, popping, rumbling, humming, or hammering noises from your water heater after trying these troubleshooting tips, it’s highly recommended to call in a plumbing professional that offers comprehensive water heater services to get the job done. At Avid Plumbing, our technicians are ready to help you with all of your water heater needs, giving you peace of mind.

For fast, reliable, and affordable water heater services, choose Avid Plumbing! Call 608-975-5545 now to speak with a technician or contact us online today.