Water Heater Making Noise: Why & What Should You Do?

Oscar Garner

By Oscar Garner

Last Updated on June, 2024

Is your water heater making a noise that’s giving you the creeps? Do you hear strange noises like popping, rumbling, hissing, and humming sounds whenever you pass your water heater? You might start sweating, thinking that there’s something wrong with it, but that’s not always the case! 

In this article, we’ll break down all the everyday noises you might hear from your water heater, their causes, and how to stop it. We’ll also be giving you the lowdown on preventing sediment build-up, changing your water heater, and so much more. 

Keep reading to find out. 

Quick Summary

  • It is normal for a water heater to make noise, but it is important to pay attention to the type of sound it is making as it can indicate potential issues.
  • The most common water heater noises include hammering and rumbling, crackling and hissing, screeching and whistling, ticking, popping, and humming. Each has its own specific causes and solutions.
  • To prevent sediment buildup, it is important to regularly drain and flush the water heater and consider using a water softener. In some cases, it may be necessary to call a professional plumber for maintenance or repairs.

Is it Normal for My Water Heater to Be Making Noises?

a plumber fixing a water heater

Absolutely. It’s typical to hear your water heater making noise since they are designed to warm up cold water for various household purposes. Just like any machine, it naturally produces sounds. 

Nevertheless, if your water heater is making noise, it’s crucial not to overlook it. When you listen closely, you can recognise the kind of sound your water heater is making and understand if it indicates that your hot water heater requires attention or servicing. 

The Common Water Heater Noises, Their Causes and Solutions

You might notice different kinds of water heater noises coming from your hot water heater tank. Here is a list of the most common water heater noises, each with its own likely reasons and the solution to fixing it. 

However, note that while you can attempt quick fixes, it’s wise to seek help from a professional to address the issue properly. 

Hammering and Rumbling Noise

Hammering and rumbling sounds are typical water heater noises, often caused by excess sediment buildup in the water tank. These mineral deposits can lead to the small explosions you hear where the sediment mixes with the heating element. 

This fix is usually easy– just flush and drain the hot water tank with a long hose to remove the mineral deposits, or try using a descaling solution to break down the existing sediment buildup inside the water heater tank. It is best to drain your tank once or twice a year. 

Sometimes, it might be due to water hammering, where the water supply rushes back through the pipes due to loose valves, causing those hammering sounds.

Adjusting the pressure using the valve can help, but you may need a water hammer arrestor or pressure-reducing valve to address the issue if the hammering sound doesn’t stop. 

Crackling, Sizzling and Hissing Noise

Crackling noises and hissing sounds are common with electric water heaters and are usually nothing to worry about if they occur occasionally. 

However, if these sounds persist, it could mean something is blocking the heating element (usually sediment), which is a more severe issue.

You might notice your heating bills go up as your water heater struggles to heat the water, with a significantly lesser ability to produce heat from the heating element.

For this issue, you will have to call a technician for help. In oil or gas water heaters, moisture buildup might be the cause of the crackling sounds. In that case, it’s best to have a technician check for any waterproofing around the tank.

Even non-electric water heaters need electricity to function, so preventing water from interfering with the electrical part is crucial. 

Sizzling sounds occur due to internal condensation dripping onto the burners, creating a sizzling or hissing sound. If condensation forms inside the tank, you might have a leaking water heater on your hands. It’s best to contact a professional plumber if tank replacement is needed. 

Ticking Noise

If you notice your water heater making noise like ticking sounds, it could be due to changes in water pressure, heat trap nipples designed to enhance efficiency, or loose pipe straps.

While it may seem scary to hear ticking noises coming from your water heater as if it’s going to explode like a bomb, most of these issues are harmless. 

Fluctuations in water pressure, if not extreme or frequent, won’t harm your water heater. Efficiency-boosting heat trap nipples are beneficial for your water heater’s operations. You can also adjust the pressure valve until the ticking noise stops. 

Loose pipe straps are minor, but it’s wise to tighten or replace them to silence the ticking and prevent your pipes from moving. Alternatively, you can slightly lower the heat to reduce pipe expansion and stop the ticking sounds. 

Screeching and Whistling Noise

a plumber replacing a water heater

High-pitched sounds like a screech or a whistle from your hot water heater often indicate loose valves letting air escape from the tank. Start by inspecting the temperature and pressure relief valve located on the side of your water heater.

If these high-pitched sounds are from this valve, immediately shut off the gas, electricity, and water to the tank, and contact plumbing services. If the noise isn’t from the relief valve, it might be the outlet, inlet control valve or nearby water lines.

Make sure all valves are fully open and check for any bends or damages in the lines that could obstruct water flow. If the lines are damaged and the loud noise persists, seek assistance from a plumber to resolve the issue. 

Popping Noise

Similar to rumbling, a popping sound typically results from limescale and sediment accumulation hot water heaters. This popping noise occurs as steam bubbles form under the sediment and burst when the water heats up. 

One solution is to use a descaling product to break down the limescale and minerals, although flushing and draining the tank may be more effective in removing built-up sediment. 

Moreover, popping noises may arise if an aluminium anode rod in water heaters is exposed to high alkalinity levels, causing it to rust. If you live in an area with particularly hard water, installing a water purification system may help reduce rust build-up. 

Humming Noise

If you hear humming sounds from your water heater, it might indicate a loose heating element or some other parts becoming loose, causing vibrations within the unit. Fortunately, there’s a simple fix for this issue. 

First, turn off the water heater to inspect and tighten all components to stop the humming sound. It’s important to let your water heater cool down for a few hours before tightening any screws or bolts to avoid burns from hot water. 

How to Prevent Sediment Buildup?

A water heater making noises can stem from various issues like water fluctuations, loose pipe straps, and leaks, but sediment buildup is often the main culprit. Water heater maintenance is crucial, so to prevent sediment build up, you must take the following measures: 

  • Drain your water heater every three to four months. Be sure to wait for it to cool down before draining to avoid burns from the hot water. 
  • Flush the water heater at least once or twice a year by filling it halfway with cold water and draining it to rinse out any sediment that may have accumulated inside. 
  • Use a water softener for your water heater to prevent sediment buildup by filtering out minerals like calcium and magnesium that create hard water.
  • If left unchecked, sediment accumulation can lead to rusting and a leaking water heater where you would have to replace it entirely. 

When to Call a Plumbing Services?

Most issues with water heaters should be handled by a trained professional familiar with water heaters. A professional plumber should perform annual maintenance tasks like flushing, especially if you lack plumbing experience. 

If you hear your water heater making a popping sound, it may need the aluminium anode rod replaced with a magnesium one. Likewise, professional inspection is necessary for crackling noises, which means that there is condensation buildup inside the tank. 

Immediate action is required for very loud screeching noises; turn off the water and power source and contact a professional. 

Additionally, a hammering sound in your water system might not be a water heater problem, but could signal a pressure issue that requires professional attention. 

How to Change Your Water Heater?

a plumber fixing a broken water heater

When a water heater starts rusting, a leak is inevitable, prompting the need to replace it. Here’s how to go about the process: 

  1. Completely shut off the water heater. Ensure water, electricity, and gas are turned off. 
  2. Open the valve at the bottom of the tank to drain all the water. Some models let you attach a hose, allowing you to drain it easily. 
  3. Confirm your tank is empty before disassembling it. Disconnect water lines, power wires, and pipes from the water heater. 
  4. Remove the old water heater and clean the area for a new one. 
  5. Install the new water heater and reconnect all water lines and pipes securely. Ensure everything is adjusted correctly as loose valves lead to noise issues. 
  6. Turn on the gas or electric power and start filling the tank. Wait for the thermostat to reach the desired temperature, which is typically around 120 degrees Fahrenheit. 



Now that you know the problem behind each water heater noise, you’ll know whether it is an issue you can handle on your own or you might need to call professional help to resolve it. 

The best course of action is to call a plumber service, especially if you feel your water heater is nearing the end of its journey. 

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