Common Water Heater Noises and How to Get Rid of Them

Learn what causes annoying water heater sounds and how US Comfort can help eliminate them.

Water heater noises can be quite annoying, especially if you can hear them in the stillness of the night when you’re trying to sleep. Worse still, some noises can be a sign of problems with your water heater. It is a good idea to get any water heater sounds investigated and corrected by a professional plumber.

Common Water Heater Noises

Knocking: Pounding or knocking noises in your plumbing are caused by shock waves. This may be caused by a water hammer effect in the pipes leading to the unit, but more often conditions inside the unit itself are responsible for the sound. What happens is minerals naturally present in the water begin to accumulate on the bottom of the water tank, forming an ever-thickening layer. This causes water trapped beneath this layer to get super-heated, producing “mini-explosions” as it eventually pops up through the sediment layer. This sound is sometimes also described as popping or cracking.

Rumbling: Rumbling noises are caused by loose sediments or debris circulating in the tank. This might be chunks of mineral buildup that have broken loose, or the byproducts released in a chemical reaction between the anode rod and your water.

Sizzling: A hissing or sizzling noise may be caused by mineral scale building up on the heating element of an electric water heater, or by condensation dripping into the flame on a gas water heater.

Cures for a Noisy Water Heater

Tank Flush: Noises caused by sediment or debris knocking around inside the water heater can be cured by flushing out the tank. In addition to quieting the noise, flushing the tank will also help improve the efficiency of your unit and the quality of your hot water.

Descaling: If you have hard water and you have not been getting regular tank flushes, significant amounts of mineral buildup may have accumulated on the tank walls. If this is the case, you will need to use chemical descaler to remove the buildup and quiet your unit. The heating element may also need to be descaled or replaced.

Tankless Water Heater: If you never want to hear annoying sounds from your hot water heater again, eliminate that noisy tank by installing a new tankless system. Tankless hot water heaters present many benefits over traditional models. Besides reducing noise, they can also lower your energy bills by eliminating the waste associated with keeping hot water at the ready day in and day out. With a tankless unit, you will never run out of hot water either—so long as you are careful to match the capacity of the unit to your hot water needs.

Need Help?

If you need help with a noisy or malfunctioning water heater, call the pros at US Comfort at 800-738-4160 .