What To Do When Your Water Heater Is Making Strange Noises

It’s late at night, and suddenly, you hear it — a strange knocking, rumbling, popping, or even a high-pitched whistle coming from your water heater. It’s enough to make anyone wonder if your water heater is about to break or burst. While odd water heater noises can be alarming, they don’t always mean you have a major problem.

In many cases, these water heater sounds have simple explanations and easy fixes. However, some noises can be a warning sign that your water heater needs maintenance, repairs, or even replacement. Ignoring strange sounds could lead to bigger issues down the road, including more expensive repairs or even a costly full system replacement.

Understanding the cause of your water heater’s sounds can help you determine whether it’s a minor issue or something that requires professional attention.

In this blog post, we’ll explore common reasons for water heater noises, steps you can take to troubleshoot the problem, and when it’s time to call the plumbing professionals at Pipe Wrench Plumbing, Heating & Cooling.

Common Causes of Water Heater Noises

Many water heater noises are often caused by minor issues, and some may not even originate from the water heater itself.

If you’re hearing strange sounds, such as banging, rumbling, popping, or whistling, here are some of the most common causes:

• Sediment buildup: Minerals from hard water can settle at the bottom of the tank, creating a layer of sediment. Hard water is particularly common in East Tennessee and the greater Knoxville, TN area. When the heating element warms and boils the water, it creates steam bubbles that get trapped under the sediment, causing popping or rumbling noises. Sediment buildup can be fixed by draining and flushing the water heater’s tank, that helps protect the heating element and reduces tank corrosion and leaks. Industry experts recommend scheduling a water heater flush annually as part of your professional plumbing system check. You can also try using a descaling product to help fight sediment buildup by breaking down mineral deposits.

• Mineral deposits on the heating element: If you have hard water, mineral scaling can form on the heating element, leading to a crackling or hissing sound as hot water moves past the deposits. This can make your water heater work harder than necessary, leading to higher energy bills and possible heating element failure.
• Expanding and contracting pipes: Hot water causes metal pipes to expand and contract, which can lead to ticking or tapping sounds as they shift. This is more common in older homes with metal plumbing and pipes. Loud banging can also signify a more serious issue known as a water hammer, which is usually caused by rapid changes in water flow or pressure. This can happen when water pressure changes direction forcefully, like when a faucet or valve is closed quickly, creating pressure waves that travel through your pipes. Water hammers can seriously damage pipes, valves, and fixtures, so if loud banging continues, you should contact a plumber to identify and correct the issue.

• Loose heating element: If your water heater’s heating element isn’t securely fastened, it may rattle or hum as it vibrates. This is usually an easy fix by tightening the heating element, but if left unaddressed, it could lead to long-term damage to the heating element or other components.
• High water pressure: A high-pitched whistling sound might be a sign that your water pressure is too high, usually from a partially closed or faulty pressure relief valve, putting unnecessary strain on your system. Excessive water pressure can also lead to leaks, pipe bursts, and damage to household appliances, so if whistling persists, schedule professional plumbing service immediately.
• Water heater age: Older water heaters experience wear and tear like any other plumbing fixture, and internal components can break down over time, leading to strange noises. If your tank water heater is over 10 years old and you’ve tried flushing the tank or getting frequent repairs, then it may be time for a replacement.

Troubleshooting Steps Before Calling a Professional

If you’re the DIY type, there are a few steps you can take to troubleshoot your noisy water heater before calling our team of expert plumbers at Pipe Wrench. Many of these fixes are simple and can help restore quiet operation, but we strongly recommend contacting a professional plumber first to ensure your safety and prevent more costly repairs or replacements in the long term.

1. Drain and flush the tank: Over time, sediment can build up at the bottom of your water heater, leading to popping and rumbling sounds. Flushing the tank can help remove these deposits and improve efficiency.
2. Check and adjust the thermostat: If your water temperature is set too high, your system may overheat, leading to unusual noises. Lowering the thermostat to a safer range (typically 120°F) can help prevent overheating or long-term damage to system components.
3. Inspect the heating element: If your water heater has an electric heating element, check to see if it’s loose. Tightening it may resolve any rattling or humming sounds.
4. Check the water pressure: High water pressure can put stress on your plumbing system, creating whistling sounds. Check that your home’s water pressure is within the recommended range of 40 to 80 PSI (or pounds per square inch) with 60 PSI being ideal for most homes.
5. Look for leaks or loose pipes: If pipes are loose or knocking against each other, they can create noise. Securing any loose connections can help eliminate unwanted sounds.

When To Call a Professional

While some water heater noises have easy fixes, others can point to a more serious issue that requires professional intervention. If you notice any of these signs, it’s time to call a licensed plumber for a water heater repair:

• Persistent loud noises: If your water heater continues to make loud popping, banging, or whistling sounds even after troubleshooting, it could signal a more serious problem.
• Signs of a failing heating element: If your water isn’t heating properly or you hear electrical buzzing, the heating element may need repair or replacement.
• Excessive rust in the water: If your hot water appears rusty or discolored, your water heater’s tank may be corroding from the inside, leading to discolored clothes or plumbing fixture buildup.
• Water leaks or visible damage to the tank: Any leaks, pooling water, or signs of deterioration on the water heater should be addressed immediately to prevent water damage.
• Unusual smells or discolored hot water: If your hot water smells like sulfur or has an odd color, sulfate-reducing bacteria or corrosion from an anode rod could be the culprit.

How To Prevent Water Heater Issues

Many of the issues that cause loud water heaters can be prevented with routine water heater maintenance.

During maintenance and a water heater check, a professional plumber will inspect the heating element, check for mineral buildup, drain and flush the tank, and inspect the piping around the unit. Schedule annual maintenance for your water heater to keep it running smoothly.

You can schedule your annual water heater and plumbing system inspection by contacting us each year, or make it even easier by enrolling in our Peace of Mind Maintenance Program. With a low monthly subscription, we’ll send you seasonal reminders to book your water heater flush and system check.

Our Peace of Mind Program is designed to simplify home maintenance and give you confidence that your plumbing and HVAC systems are in top shape. The maintenance plan includes an annual water heater flush, a complete plumbing system inspection, and biannual HVAC checks.

Want to learn more? Explore all the benefits of our Peace of Mind Membership Program or contact us today to get started.

And if your home has hard water, consider installing a water softener. Hard water contributes significantly to sediment buildup and mineral scaling inside your water heater, which can accelerate wear and tear. A water softener can help prolong the life of your system and improve the overall water quality in your home.

Contact Pipe Wrench Plumbing, Heating & Cooling for Water Heater Services

Water heater noises can be unsettling, but understanding the cause can help you determine the best course of action. While some minor sounds are nothing to worry about, persistent or unusual noises could indicate a larger issue. Performing basic troubleshooting can often resolve the problem, but if you notice signs of a failing system, it’s best to call a professional.

At Pipe Wrench Plumbing, Heating & Cooling, our experts provide fast, reliable water heater repairs and replacements to keep your home running smoothly. With same-day service guaranteed (or the visit is free!), you can count on us to restore your hot water quickly and efficiently.

Our team is dedicated to providing the best customer service in the Greater Knoxville, TN, area, and we’ve been voted the best plumbing company in Knoxville for seven years, so call us today for expert water heater services.

Contact us today to schedule water heater repair, replacement, or maintenance in Knoxville, TN.