Noisy Hot Water Heater? Here’s Why, Plus What You Can Do About It


A noisy water heater can be a sign that you need to call a professional plumber to check the unit. But not all noises mean that your water heater is broken.

What are the sounds you should be aware of? Knowing these sounds and what they mean could help you fix the noises.

Humming sounds

If you have an upper electric water heating system, you may have heard this noise. The sounds can be due to vibrations as cold water flows into the water tank, causing the upper electric heating element to make a humming noise.

Also, your water heater could be making humming noises when water struggles to get through the line. Lastly, loose components in your hot water heater could also cause humming noises.

Knocking or Hammering Sounds

If you hear knocking or hammering coming from your hot water heater, it’s most likely caused by a loose connection in the plumbing. If you’re having trouble hearing it, it could be because you have an older hot water heater that uses a threaded connection instead of being attached with a hose clamp or pipe connector.

Gurgling, Cracking, or Popping Sounds

When you hear gurgling, crackling, or popping noises from your hot water tank, it could mean there is a deposit build-up in your water tank. If not addressed, this build-up will cause electrical resistance, affect the thermostat, and cause the tank to rust and crack.

These sounds may also mean that your water tank is contracting and expanding during regular operation. A popping sound may be due to water forcing itself through a small hole.

Screeching or Screaming Noises

Screaming or screeching noises are obvious signs of pressure problems caused by improperly opened valves. Water will force itself through partially open valves, increasing pressure and generating screaming or screeching noises. A professional plumber may need to inspect the valves to regulate and fix the pressure issue.

Kicking or Tapping Noises

Your water heater will always alert you when something is wrong, just like a toddler makes noises when unhappy. Tapping noises are clear indicators of three possible things; sediment build-up in your water heater, faulty valves, or expansion and contraction as water is heated in the tank.

Bubbling Noises

Bubbling sounds indicate a serious issue with your hot water system. Your heater could be overheating, or there is pressure build-up. These two possibilities could mean higher utility bills and could put your family at risk. It is best to call a professional plumber as soon as you hear bubbling noises in your water heater.

If your water heater is more than 10 years old, it’s a good idea to have it checked by a professional. Over time tanks start to rust and corrode, causing many problems. If your tank is starting to show signs of wear and tear, it’s a good idea to get it replaced.  If you’re concerned, contact a plumber so that he can correctly fix the problem.