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Is Your Water Heater Making Noise? Follow These Simple Tips

There’s nothing worse than being constantly aggravated by an annoying sound from your noisy water heater. When a situation like this arises, there are simply steps you can take to resolve the problem. By fixing the problem yourself, you can eliminate an expensive and unnecessary expense.

There are several different sounds that your water heater can make when maintenance or repairs are needed. It’s important to know the difference between them and what they actually mean, so you can get your system up back to working great again. These sounds include:

  • Humming
  • Knocking
  • Screeching
  • Tapping
  • Other Weird Sounds

Humming Sounds

In most electrical water heater tanks, the element is placed in a vertical position. As a result, when the water flows around the element, it can cause vibrations which transform into the sound of humming. How do you fix this problem? The best way to stop the humming is to simply tighten the element. This is an effective way to solve this issue when your water heater is making noise.


Also known as “water hammering”, this hot water heater knocking sound can occur when the water flowing through your pipes is instantly turned off. Whether it be due to the facet, the toilet or the shower, the abrupt stop of water flow causes the pipes to move. Although this movement will more than likely do no harm to your pipes, it can cause damage to your walls overtime. To eliminate this hot water heater knocking sound, you can simply invest in a water hammer arrestor and install it correctly.

It shows sediment that collects at the bottom of your hot water water heater. flickr / Hadley Paul Garland

Another reason your water heater may make a knocking or even a popping sound could be due to sediment accumulating at the bottom of the tank. Sediment originally comes from the water itself and overtime accumulates at the bottom of your water heater. As a result, this blockage makes your water heater work inefficiently and puts the system at risk of damage. To eliminate the sediment, you will need to flush your water heater tank. For instructions on how to flush your water heater, refer to the section below.

Hissing or Screeching

When your water heater making a hissing noise or a screeching sound, the problem is ultimately caused due to a valve that is not completely opened. As a result, water gets forcefully pushed through a small hole causing your water heater to make a hissing or screeching sound. To resolve this problem, you need to inspect the valves throughout your waterline. Once you open the valve completely, the hissing and/or screeching should not be an issue anymore.


Heat traps and check valves are commonly found in the pipes of many water heaters and are installed to keep water from traveling in the wrong direction. Overtime, these traps and valves can cause tapping or ticking sounds. For most homeowners, this can become quite annoying. To eliminate this pestering sound, you can invest in a dielectric nipple and replace the heat trap with it.

Other Weird Sounds

Tankless water heaters are known for causing their own unique sounds. First, clicking sounds are perfectly normal with tankless water heaters just as they are with regular water heaters. However, with tankless water heaters, the clicking sound is due to the regulation of water by the flow switch. When there’s calcium deposits being deposited as a result of the use of hard water, the tapping sound can become quite loud. By simply investing in a water softener, this problem can be resolved.

Other reasons why your tankless water heater might be making irregular sounds could be due to either a filthy burner fan or irregular gas combustion as a result of a leak. But generally speaking, tankless water heaters in comparison to regular water heaters tend to make less overall noise. For people that are annoyed by these sounds, that’s good news.

Is Your Water Heater Making Noise? Then Flush Your Water Heater !

Like mentioned above, if your water heater is making noise, it might be because of the sediment that has settled on the bottom of the tank. To quiet down your system, it’s important to flush your water tank out at least once a year. For the proper way to flush your tank, watch this video and follow the steps below.

  1. The first thing you need to do is to get yourself a pair heat resistant gloves. This will help protect you from possible injury.
  2. Next, it’s important that you shut the water down. For homeowners with a gas operated water heater, simply choose PILOT mode for the temperature. For homeowners with an electric water heater, you’ll need to head to the circuit breaker to turn off your water. In addition to this, you’ll also want to shut off the cold-water valve as well.
  3. Your next step is to let your water heater cool down. This is an important in preventing injury. This will take approximately 30 minutes.
  4. Once your water tank has cooled down, you’ll now need to attach your garden hose to the drain valve. If you are unfamiliar as to where this is, you can locate this at the bottom of your water hater tank.
  5. After you have connected the hose, it’s time to place the end of it someplace safe where the water and the sediment can drain. To avoid a vacuum from forming during the draining process, it’s essential that you open a hot water faucet. This can be the facet from either the kitchen sink or the bathroom tub.
  6. Find the small slot on the valve of your water heater. Once you locate it, slowly turn it. Now, you’ll want to locate the pressure relief valve and pull thee small tab out. The draining process will now begin.
  7. Once you’ve let your tank drain out, you’ll want to wash out the rest of the lingering sediment stuck inside the tank by turning the cold water valve back on.
  8. Shut the drain valve once you see clean, crystal clear water draining from the tank. This means all the sediment has been removed from your water heater. You can now let your tank fill up with clean water and turn your heating unit back on.

If you take advantage of the information listed above, you can ensure that when your water heater is making noise, you can eliminate the noisy water heater while also helping extend the life of your system as well.

Kevin L. Sharp

veronica M hernandez

Tuesday 22nd of January 2019

My tankless gas water heater make a terrible noise when the air condition start working however the a/c and heater are electric. I don't understand why are they connected.