A clicking water heater is surprising, and for many homeowners, it’s a sound that raises questions.
Is something broken?
Is it dangerous?
Or is it nothing to worry about at all?
While some clicking noises are harmless, others indicate developing problems that need attention before they turn into costly water heater repairs.
Understanding what’s behind that sound is the first step to fixing it.
In this blog, we’ll break down the most common reasons water heaters click, explain how to fix them, and share when it’s smart to call a plumber to keep your system running safely and efficiently.
Why your water heater clicks
Expansion and contraction
When your heater warms up, the metal components inside expand. As the unit cools down, it contracts. This natural movement may create light clicking or tapping sounds, especially in older units or during seasonal temperature changes.
This type of clicking is harmless in most cases, though it can become louder over time.
Sediment buildup
If you hear frequent clicking or popping sounds, sediment buildup may be to blame. Over time, minerals from hard water settle at the bottom of the tank.
As the water heats, bubbles push through the hardened layer of sediment, creating a clicking or popping noise. Traditional tank-style heaters need flushing regularly to prevent this.
Mineral deposits on heating elements
Minerals often collect on the heating elements in tankless and electric heaters. Water flowing through these partially blocked areas can make a sharp clicking or tapping noise. This buildup creates sound and forces the system to work harder, which reduces efficiency and shortens the unit’s lifespan if ignored.
Loose plumbing connections or components
Sometimes the clicking doesn’t come from inside the tank at all. Loose valves, fittings, or pipes may shift slightly as water pressure changes, producing a clicking or rattling sound. If these connections aren’t secured, they can eventually lead to leaks or wear on the system.
How to fix a clicking water heater
Once you’ve identified what might be causing the clicking noise, there are steps to address the issue. Some fixes are simple, while others are better left to a professional plumber, especially if they involve gas lines, electrical components, or internal parts of the unit.
Expansion and contraction
If the clicking is light and happens mainly when the unit heats up or cools down, it’s usually harmless. Insulating the pipes or adding padding around mounting brackets will often reduce the noise. It’s smart to make sure the heater is installed securely so that the normal expansion of metal parts doesn’t cause unnecessary movement.
Sediment buildup
Sediment buildup is among the most common causes of clicking in traditional tank-style water heaters. Flushing the tank helps remove that hardened mineral layer and quiets the system.
Start by turning off the power or gas supply, letting the water cool, and draining the tank completely. Then, flush it with clean water to rinse out sediment. If the tank needs servicing or the buildup is heavy, it’s best to call a professional plumber for a thorough flush and inspection.
Mineral deposits on heating elements
Clicking can come from mineral deposits on the heating elements for tankless and electric heaters. A professional descaling service removes this buildup and restores proper water flow. In areas with hard water, installing a water softener or scheduling regular maintenance helps prevent future deposits and keeps your unit running quietly.
Loose plumbing connections or components
If the clicking comes from valves, fittings, or nearby pipes, gently tightening the connections may sometimes stop the noise. Be careful not to overtighten, as this may cause leaks or damage.
If you’re unsure where the sound is coming from, or if tightening doesn’t help, a plumber can inspect the system to secure loose parts and ensure nothing is wearing down behind the scenes.
When to call a professional plumber
If you’re unsure of the cause of your clicking water heater — or if the noise keeps coming back after basic maintenance — it’s time to call a licensed plumber to see if you need a water heater repair. Persistent clicking may signal deeper issues like heavy sediment buildup, failing heating elements, or internal corrosion.
These problems won’t go away on their own and lead to bigger headaches down the road, including leaks, reduced efficiency, or even complete failure. A professional plumber has the tools and experience to diagnose the source quickly and fix it correctly the first time.
You should also call a plumber if you’re uncomfortable flushing the tank, working with electrical components, or handling gas lines. Water heaters involve multiple systems; even a small mistake can create safety risks.
Regular professional maintenance fixes clicking noises and extends the life of your heater, improves performance, and helps prevent expensive emergency repairs later. If the clicking sound is frequent, worsening, or accompanied by other warning signs, scheduling an inspection is the safest move.
Schedule annual maintenance
To keep your water heater in top condition and minimize the need for water heater repair, schedule annual maintenance with a trusted plumber. Regular inspections help catch small issues, like minor sediment buildup or loose fittings, before they become serious problems.
A plumber can flush the tank, test temperature and pressure valves, and ensure all connections are secure. Preventive care eliminates unwanted noises, extends your system’s lifespan, and keeps your energy bills lower year-round.
Get expert help from Salisbury Plumbing
A clicking heater may seem minor, but it’s often a sign your system needs attention. Whether it’s sediment buildup, loose components, or a more serious issue, getting help from experienced professionals is the safest way to protect your home and avoid costly repairs down the road.
The team at Salisbury Plumbing has the knowledge and tools to diagnose problems quickly and fix them correctly. From routine maintenance to complete system repairs and replacements, we keep your plumbing running efficiently and reliably.
Don’t let a small clicking sound turn into a big headache. Contact Salisbury Plumbing today for expert water heater service and trusted plumbing solutions you can count on.
