Water Heater Making Noise? Here’s What You Should Know

Technician servicing a white tank water heater

Imagine enjoying a quiet and peaceful shower, only to be disrupted by hissing, popping, and other unsettling sounds from your water heater. Is it a plumbing disaster waiting to happen? Maybe not.

Understanding that your heater is a complex system with intricate components can help demystify the strange and intrusive noises it makes — and we’re here to help you decode them. By carefully listening to your water heater, you can identify when it’s time to seek professional help or do a few simple maintenance tasks to keep it running smoothly.

Is It Normal for Water Heaters To Make Noise?

Absolutely. Not all sounds from your water heater are bad. Water heaters making noises is common and shouldn’t immediately be considered an emergency. In most cases, the noises may be part of its normal operation as it heats water for your showers, washing machine, dishes, and other household needs. 

These sounds can vary from a soft hum to minor hissing, popping, and knocking. However, understanding the reason behind the strange sounds of your water heater is the key to alleviating your concerns or deciding to have your system professionally repaired to prevent damage to your unit.


A buildup of sediment in your system can lead to popping sounds. This is common in water heaters, especially in areas with hard water. When steam bubbles form under the sediments, they burst through, making a popping sound.

By flushing your system and draining the tank to remove the sediment, you can restore your water heater and eliminate popping sounds.

Banging & Knocking

If you hear loud banging or knocking sounds, it could be a water hammer issue. Water hammer is the name given to the sudden and forceful shockwave that occurs when the flow of water abruptly stops or changes directions.

This pressure imbalance is strong enough to burst pipes in your system, so it’s important to seek professional help in addressing it.


If you’re hearing hissing sounds, chances are you have an electric water heater. When sediment builds up, covering the lower heating elements in your tank, a hissing sound is often the result. Over time, the sediment accumulates, creating a barrier between the heating element and the water.

This causes the water to boil and create steam. The hissing sound is created when the steam escapes the sediment. Flushing the tank and removing the sediment will eliminate the source of the hissing and restore your system’s efficiency.


If your water heater is humming, it’s time to call a plumber. Persistent hums in your system often indicate a loose heating element. Consulting a professional can help clarify the source of the hum and address any safety risks and system inefficiencies.

Water Running

Water entering your tank can produce the running water sounds you hear. However, consistent running water sounds could signal a leak or burst pipe that needs immediate attention.

Why Choose Us?

While water heater noises can be frustrating, it’s never recommended to ignore them. By resolving your water heater noises, you’re ensuring the longevity of your system while preventing the risk of costly damages. 

Avid Plumbing is committed to maintaining your home’s comfort with unmatched water heater services, including installation, repair, and maintenance. With same-day service, fully stocked trucks, and competitive and honest pricing, we strive to deliver efficient, prompt, and quality water heater solutions you can trust.

Schedule water heater services in Madison, WI, with Avid Plumbing by calling 608-661-2843 today.