What Do Those Bizarre Water Heater Noises Mean?

What Do Those Bizarre Water Heater Noises Mean?

Your water heater should be an unsung hero of your home. It heats the water that you use to shower, do laundry, wash dishes, and keep your home warm during winters. But when it starts to create some odd noises, it can be quite a scary experience. Gasping, rumbling, sighing, banging, and sizzling from the water heater can indicate anything from sediment buildup to an impending failure. So what is causing those weird sounds? Read on to find out.

Rumbling Sound

One of the most common noises from a water heater is a rumbling sound. This sound results from the reheating of water inside the tank. Minerals and sediments from hard water often collect at the bottom of the tank over time. As the water heats up, the minerals and sediments move around, causing the rumbling sound. A flushing could be needed to alleviate the sediment buildup in the water heater. Afterward, if the noise persists, the bottom of the water’s tank may be corroding and the water heater may require a replacement.

Whistling Sound

Another familiar noise that is caused by water heaters is a whistling sound. This sound results from a malfunctioning relief valve. A relief valve is installed on a water heater to prevent the tank from overpressurizing and exploding. A malfunctioning relief valve or a valve that fails to close after releasing pressure will make a whistling sound. Releasing some of the pressure from the valve or phoning a plumber for repair may resolve the problem.

Banging Sound

Sometimes, you hear a banging sound from your water heater. At times, this sound is triggered by a problem with the heating component. The sound signifies overheated water, which causes high pressure, hence the sound. In such a situation, we advise that you turn off the water heater and phone a specialist immediately. If your heater is making banging noises, chances are that the heating component is damaged, resulting in either repair or replacement of the unit.

Crackling Sound

Another noise you could be hearing is a crackling sound. The popping and cracking sounds from your water heater are frequently the result of sediment buildup on the heating element. Expect the noise to stop once you flush the tank with clean water. The noise could also signify a leak in the tank. A leaking tank usually pops and cracks accompanied by the sound of hissing or whistling. If that’s the case, call for an immediate repair or replacement of your water heater.


We all rely on our water heaters to get us through the chilliest of days. And when it malfunctions, it can be quite a startling experience. While some noises could be the sign of some sediment buildup and are warning signs, some others could signify something more severe. If your water heater is making strange sounds, it's advisable to call in a professional plumber. They can diagnose the problem, determine the source, and fix it accurately and adequately, ensuring you have hot water for your home or commercial facility.

If you hear strange noises coming from your water heater, it is important to contact a professional plumber right away. Mike's Plumbing of SWFL provides expert diagnostics and repairs for water heaters in Southwest Florida. Ou team of professionals can provide efficient service and quality workmanship to get your water heater back up and running in no time.