Are you losing sleep over the strange symphony coming from your noisy water heater? From hissing and popping to knocking and clicking, a noisy water heater can be more than just a nuisance. It could be a sign that your water heater needs some maintenance or repair. This guide will help you understand what is causing all the water heater noise and how to quiet it down safely and effectively.

Understanding the Racket: Common Causes of Water Heater Noise

Even a well-functioning water heater will make some noise while heating your water. However, frequent loud or unusual noises can be signs that it’s time for some water heater maintenance. Here’s what the most common water heater noises might mean:

  • Crackling or Hissing Noise: A hissing sound could mean something is in the way of your water heater’s heating unit.
  • Popping Noise: A popping sound usually means there is sediment buildup inside the tank, likely from hard water or rust.
  • Knocking/Hammering: A hammering sound could be from sediment buildup or something called water hammer, which is caused by water flooding back through your pipes after water is turned off.
  • Clicking/Ticking: Sudden changes in water pressure often cause this sound but it can also be from loose pieces within the unit.
  • Humming Sounds: These are typically due to vibrations from loosening parts.
  • Whistling or Screeching: When your water heater is making noises that sound like high-pitched screeching, it is usually due to loose valves letting air out of your tank.

Silence the Sounds: Troubleshooting Your Noisy Water Heater

If your hot water heater is making noises and you want to save money by trying the DIY approach first, here are a few remedies you can try. However, if these solutions don’t do the trick, you’ll need to call for professional plumbing services.

It is always better to have a professional figure out why your hot water heater is making strange noises than to let it go until disaster strikes and you need a full tank replacement.

If You Hear Hissing or Crackling Noises:

Crackling and hissing sounds are perfectly normal to hear every once in a while in electric water heaters. If the sound is happening a lot, you may need to drain your tank to see if there is something blocking your heating element.

If you have a gas water heater, the crackling sounds are probably due to moisture build-up. Especially if you see water pooling at the base of your unit, you’ll want to call a technician.

A leaking water heater can be dangerous. Even if your water heater doesn’t primarily run on electricity, it still needs it to work. The last thing you want is water messing with your unit’s electrical parts.

For more tips on how to deal with leaking hot water heaters, read “Water heater leaks are sneaky. But we’ve outsmarted them.”

For Popping Sounds:

Popping noises are usually a sign you need to flush your water heater tank. We recommend calling a professional to flush your tank at least once a year to prevent sediment build-up. Once your water heater tank is clean, the popping sound should go away.

If you live in an area with hard water, you might also want to install a water purification system to reduce rust and sediment build-up. You could also look into replacing your water heater’s anode rod. It is a sacrificial part that reduces the build-up of rust on the water tank.

When You Hear Knocking or Banging Noises:

If a bunch of sediment and mineral deposits build up in your water heater tank, they may mix with the heating element and create mini-explosions. Those explosions are the loud noise that sounds like knocking or banging coming from inside your water heater. Flushing your hot water heater will usually fix the problem.

The other possible cause is called water hammer.

Water hammering occurs when water is turned off and suddenly changes directions and forcefully flows back through the pipes. A water hammer arrestor, which you can find at most hardware stores, can help with this issue. Water hammer can be strong enough to make your pipes burst though so it’s probably best to have a trained technician come and check it out.

For Humming Sounds:

A humming noise can be the result of a blockage in the combustion air inlet. This is one that you don’t want to try to DIY. Give a professional plumber a call instead.

If You Hear Whistling or Screeching:

High-pitched sounds like whistling or screeching are usually from loose valves releasing air from the water tank. You could take a look at your water heater’s pressure-releasing valves and temperature valves to see if there is a leak. However, it’s best to just have a plumber come look at it for you.

Be Proactive With Your Water Heater

Regular maintenance is key to preventing noise and extending your water heater’s life. At the very least, you’ll want to have a professional flush your hot water heater at least once a year to minimize sediment buildup (which, you may have noticed, is a common theme in water heater noises).

Even though some noise from your water heater is normal, if you are consistently hearing strange water heater noises it’s time to figure out what’s causing all the racket. Prevention is always better, and cheaper, than a big repair.

Use our checklist to determine if it is an issue you should try to tackle on your own or if it is time to call a professional.

If you’re tired of listening to your water heater’s humming, rumbling or tapping sounds and live in Livermore, CA or the surrounding areas, give us a call at (925) 492-7672. One of our fast, friendly water heater pros will come quiet your water heater down for good.