Buzz, Hum, Screech! Why Is My Water Heater Making Noise?

Are you curious as to why your water heater might be making noise? Should you perform maintenance, call a plumber, or just ignore the sounds? Worried that it might be on its last leg? We all know water heaters can be expensive to replace so it’s good to know what sounds might be serious and which ones might not be.

Water heater noises are pretty common, and they are usually an indication that you will have to at least do something about it. The list below are the most commonly reported water heater noises, as well as solutions that you as a home owner might be able to implement. We hope this helps you determine what steps you need to take to keep your water heater running at its best.

Your Water Heater might be Making Rumbling, Crackling, or Popping Noise

Water heaters heat the water in the tank. But did you know as the water heats, bits of sediment are boiled out of the water, and these bits of sediment collect on the element tubes and anode of your water heater. Layers of sediment build up inside your tank, trapping water underneath the layers of sediment. As the water heats up, it bubbles up through the sediment deposits, sometimes breaking off the sediment and causing it to become loose in the tank. This popping or crackling sound you are hearing is the action of hot water forcing its way through the layers of sediment that has accumulated. There are some home owners who report hearing a rumbling sound and wonder what it is. The rumbling sound comes from broken off chunks of sediment swirling around inside the tank.

What Can You Do To Help Fix This?

If you hear your water heater is making crackling, popping or rumbling sounds, then it’s a problem with built up sediments in the tank. To fix this, if your water heater is under ten years old, you can get away with using a deliming mixture to flush the sediment out of the tank and then flush and drain your water heater.

We recommend flushing and drain your water heater once a year to prevent this problem. Too much sediment reduces the efficiency of your water heater and can reduce the life of your water heater. A properly maintained tank water heater can work well for 15 years, but an unmaintained water heater will usually have catastrophic failure in about 10 years.

When you do flush the tank if it’s still making noises, you may want to check the thermostat. If your thermostat is set at 125 degrees or higher, the noises may be created by the expansion and contraction of the tank from the heat. Reduce your thermostat setting to 120 degrees or lower (this is recommended to prevent accidental scalding) and then listen to see if the noise continues.

Please note that if your water heater is over ten years old, you may actually cause problems within the tank if you try to delime and flush. It’s probably best to start researching what type of water heater you want next and to prepare to replace the water heater soon. South End Plumbing can help you in selecting the right type of water heater for you if you’re ready for a replacement.

Is Your Water Heater Humming?

Now if your hearing a humming noises, this most likely means that your water heater element is loose, causing the water flowing around the element to cause vibration that sounds like humming. This type of noise is of no concern. When the humming noise bothers you and you want to correct it, you can have a plumber tighten the element. Tightening the element is also something the home owner can do themselves if they are handy.

What If Your Water Heater Is Making A Hammering Noise?

May plumbers call this “water hammering”. This is literally a knocking of the pipes as they are mounting hitting the wall. This can happen because the pipes are not securely anchored and they are slapping the studs or the interior of the wall because of water pressure. It can be caused by abrupt turning on and off of water also, such as a toilet being flushed or water pump that does not have a holding tank to distribute the flow of water at a slower rate. Thankfully this is not an urgent issue, but it is possible that you might end up with some damage after time if not fixed. This problem does nothing to your water heater in any way, so don’t worry about replacing water heater because of it- that’s not the source of the noise or the cause of the knocking. To fix this you can have a plumber install a water hammer arrestor which should take care of the issue.

What If You Hear A Hissing Noise At Your Water Filter?

Hearing a hissing sound usually indicate a leak. You’ll want to look for water or steam coming from the water heater or a pipe leading to it. A leak of this nature most of the time requires repair by a professional plumber. In cases where the water heater is old, it may be better to do a water heater replacement. Make sure you aren’t incurring water damage somewhere, and then call South End Plumbing to service your water heater.

Do You Hear Your Water Heater Making A Screeching Sound?

Those high pitched sounds are water being forced through a small opening under great pressure. This is usually caused by a valve that’s not opened all the way.  The valve in question may be at your water heater or it might be closer to faucets in your home or near an appliance. Listen carefully to hear where the noise is coming from to determine the location of the valve. To fix this you might need a new valve at the water heater itself, make sure this is something your familiar with or have a professional plumber do this because there’s high risk of injury due to steam burns. If the loudness of the noise is closer to a faucet or appliance, you may be able to replace the valve yourself if you’re handy. To proceed just make sure to turn off the water to that sink or appliance, then adjust or change out the valve.

Is Your Water Heater Making A Ticking Sound?

When your water heater is making a tapping or ticking sound that usually comes from heat traps or check valves that have been installed to encourage water to flow in the correct direction. This type of noise might also come from water heating and cooling in the pipes.  Some home owners are picky and the ticking or tapping noise them, in that case you can replace the heat trap with a dielectric nipple. There are some cases where this does not guarantee the noises will stop. Knowing this though, just realize that this is not indicative of any real problem, if you only occasionally hear it when you’re in the room where your water heater is located it’s going to make the most sense to try to ignore it.  As they often say, “if it ain’t broke, don’t try to fix it!”.