Is Your Water Heater Making Strange Noises?

We take our water heaters for granted, this is one of the hardest working appliances in our homes, but it’s out of sight and thus out of mind most of the time. Supplying hot water to your home on a 24/7 basis takes its toll, but usually, you will not hear any noise from your water heater. But, perhaps you’ve recently noticed some new sounds, such as popping, hissing, banging, screeching, ticking, or clanking noises? This should be a cause for concern; something is wrong with your water heater, and the type of sound it’s making is indicating the possible cause of the problem.

Popping or Clanking Sounds

If you can hear any loud popping, clanking, or cracking noises coming from your water heater, the likely cause is a buildup of minerals inside the unit. Most of our nation is supplied with hard water that contains a high concentration of dissolved mineral content. Water is a very effective solvent; it can dissolve a wide variety of materials, including rock and soil, that it passes through on the way to your home. The water hardening minerals include calcium, magnesium, and iron that can play havoc with your plumbing and water using appliances.

The popping sound that you can hear could also be a warning that you have a thick layer of sediment forming at the bottom of the water tank. This prevents an efficient heat transfer to the water, and this decreases the water heater efficiency. This problem will only get worse over time, the heating costs will be increased, and the useful lifespan of the appliance will be shortened. It’s also more likely that the water heater will fail, and this will result in downtime until you get the unit repaired or replaced.

A local licensed plumber can correct these problems for you by carrying out some essential annual water heater maintenance. This will make your water heater more efficient, reduce the chances of a breakdown, and help your appliance to last longer.

Subtle Hissing Noises

This is a common phenomenon found in electric water heaters, and it’s another warning of a buildup of mineral deposits inside the unit. When the sediment and minerals cover the heating electrodes, they struggle to heat up effectively. A local plumber can clear the sediment and minerals away or simply install a new water heater for you if a repair isn’t economically viable.

Banging or Booming Sounds

If you start up your water heater and you can hear a very loud banging or perhaps a booming sound, you need to turn the unit off and contact your local licensed plumber. The water heater needs an emergency repair, and it should not be used until that repair has been completed. The cause of these two types of noises is the fuel source for your water heater. The gas or oil is actually reigniting when the water heater burner starts up. If this problem isn’t corrected, the chance of an explosion is significantly increased.

Another possible cause of a banging or booming sound could be a higher than usual thermal expansion insider your water heater. This often occurs when your water heater needs to reheat a very large volume of water. As an example: if you needed to refill the storage tank after it’s been fully depleted when returning home from a long vacation. If you can hear these types of sounds, it’s important to get a professional plumber to look at the water heater. In some cases, this problem can be corrected by the installation of an expansion tank.

Screeching or Whistling Noises

These are very strange noises, but they are actually quite benign, and they indicate a problem that’s simple to fix. At your water heater inlet, you will see a control valve, and if this is partially open, you will hear these types of noises. Simply close the control valve fully, and you should notice that the noise has gone away.

Another possible cause is the exhaust flue; if the flue is not sized correctly, a resonant frequency is created with a tankless water heater. The interaction is very noticeable when you turn the temperature up, and the screeching noise increases. The best way to deal with this problem is to get a local plumber to resize your exhaust system.

Ticking, Clicking and Tapping Sounds

These types of sounds are often barely perceptible, and for the most part, they are considered to be normal water heater noises. These sounds are caused by the thermal expansion that occurs inside your water heater during normal operations. The usual source is the heat trap, this is installed in your hot water supply, and it lies in the pipes downstream from your water heater.

Most people learn to ignore these types of water heater sounds, and they fade into the background as ambient noise. These noises are no cause for concern, but if you do find them to be distracting or annoying, you can take steps to remove them. A local licensed plumber can check the routing from your water heater and examine the hot water pipes. Sometimes if the hot water has to pass through openings that are too narrow, it can create extreme examples of these types of sounds. A plumber could locate those openings and expand them, allowing the hot water to flow more easily. In most cases, this will get rid of the sounds completely and help you to get some peace and quiet.

The Importance of Water Heater Maintenance

The water heater in your home is a hard working appliance, and it makes sense to take care of it. This is why it’s a great idea to schedule some annual maintenance to ensure that your water heating is working efficiently. All of the problems discussed in this article can be identified and fixed during a regular maintenance visit. If your water heater needs attention, always call a local licensed plumber for expert help and advice.

By Giovanni Longo President Flood Brothers Plumbing
Giovanni Longo is a 3rd generation master plumber who has been practicing his craft and trade in the greater Los Angeles area for well over a decade and a half. A plumbing and hydraulics-engineering innovator, Giovanni’s particular world-class expertise focuses on dealing with challenging sewer system designs as well as resolving complex commercial and residential draining issues. As a certified Flood Mitigation expert, he is also well versed in a wide variety of water damage and remediation solution.