Water Heater Maintenance: How to Extend the Life of Your System

Your water heater works every day, usually without much attention—until the hot water runs out, the tank starts leaking, or a component fails.

Routine water heater maintenance is less about constantly tinkering with the equipment and more about controlling the things that wear it down over time: sediment, mineral scale, corrosion, excessive heat, pressure, leaks, and neglected safety components.

Tank and tankless systems require different maintenance, but the goal is the same: keep heat transferring efficiently, protect the equipment from internal damage, and catch small problems before they turn into a loss of hot water or a major leak.

This guide covers what homeowners can safely check, which maintenance tasks require more care, and when professional water heater service makes sense.

Why Water Heater Maintenance Matters

Water heaters operate under demanding conditions.

A tank-style unit continuously stores dozens of gallons of hot water while exposed to minerals, pressure, and corrosion. A tankless system repeatedly heats water as it passes through a compact heat exchanger, where scale buildup can reduce performance over time.

Maintenance helps protect the system from several common problems:

• Sediment collecting in a tank
• Mineral scale inside a tankless heat exchanger
• Internal tank corrosion
• Failed safety components
• Small leaks that worsen over time
• Excessive temperature settings
• Restricted combustion airflow or venting
• Worn valves and connections
• Reduced heating efficiency

Maintenance cannot make a water heater last forever, but it can help the equipment operate under better conditions throughout its service life.

Just as importantly, regular inspection gives you a chance to notice deterioration before the first warning sign is water on the floor.

Start With a Simple Visual Inspection

You do not need tools to perform one of the most useful maintenance steps.

Look at the water heater.

Check the floor, fittings, pipes, valves, and visible connections around the unit.

Look for:

• Water beneath the tank
• Rust streaks
• Corrosion around fittings
• Moisture at pipe connections
• Dripping valves
• Damp insulation
• Mineral deposits around joints
• Discoloration near the bottom of a tank
• Signs of previous leakage

For tankless systems, inspect the visible water and gas connections as well as the area below the unit.

A small amount of corrosion around a fitting may seem minor, but water leaks rarely improve on their own.

The source matters too.

A leaking pipe connection may be repairable. Water coming directly through the body of a storage tank can indicate internal tank failure and is a much more serious problem.

Check the Water Temperature Setting

Water temperature affects comfort, energy use, safety, and the amount of stress placed on the water heater.

For many homes, a setting around 120°F provides a practical balance between hot-water performance and reducing scald risk, although the correct setting can vary depending on the household, equipment, manufacturer recommendations, and other needs.

Higher temperatures can:

• Increase energy consumption
• Increase scald risk
• Accelerate mineral buildup
• Place more thermal stress on components

If the water suddenly becomes much hotter or colder than expected without anyone changing the setting, the issue may involve the thermostat, heating element, burner controls, mixing valve, or another component.

Do not repeatedly increase the temperature setting to compensate for a water heater that is no longer producing enough hot water. That can mask the actual problem without correcting it.

Flush Sediment From a Tank Water Heater

Sediment is one of the biggest maintenance concerns for traditional tank-style water heaters.

Minerals naturally present in the water can settle at the bottom of the tank as the water is heated.

Over time, that buildup can become substantial.

Why sediment matters

In a gas water heater, sediment can create a layer between the burner and the water being heated.

In an electric water heater, buildup can surround the lower heating element.

Either way, the system may have to work harder to transfer heat.

Heavy sediment can contribute to:

• Rumbling or popping noises
• Reduced efficiency
• Less usable hot water
• Longer recovery times
• Stress on the tank
• Premature component wear

Periodic flushing helps remove accumulated material before it becomes excessive.

How often should a water heater be flushed?

There is no perfect schedule for every home.

Water hardness, water quality, hot-water use, tank design, and manufacturer recommendations all affect how quickly sediment accumulates.

An annual flush is common preventive maintenance for many tank systems, but homes with hard water may need more frequent attention.

If a tank has gone many years without being flushed, use caution before suddenly attempting an aggressive DIY flush. Sediment can sometimes be masking deterioration in an older tank, and aging drain valves may not reseal properly after being opened.

If you are unsure about the condition of the equipment, have it evaluated before disturbing old valves or heavy buildup.

Listen for Popping or Rumbling From the Tank

A water heater should make some noise while heating, but loud popping, cracking, or rumbling can point to sediment accumulation.

When water becomes trapped beneath a layer of mineral deposits, heating can create bubbles that push through the sediment.

That movement can produce the familiar rumbling sound.

Noise does not automatically mean the tank is about to fail, but it is worth investigating—especially if it is getting louder or is accompanied by:

• Reduced hot-water capacity
• Longer heating times
• Older equipment
• Discolored water
• Leaks
• Changes in performance

Ignoring heavy sediment can allow the system to continue operating under less efficient and potentially more stressful conditions.

Inspect the Anode Rod in a Tank Water Heater

One of the most important parts of a conventional water heater is also one most homeowners never see.

The anode rod is designed to corrode so the steel tank does not.

This is why it is sometimes called a sacrificial anode.

Instead of corrosion attacking the tank itself, the anode rod gradually deteriorates.

Eventually, the rod can become depleted.

Once that protection is gone, the inside of the tank becomes more vulnerable to corrosion.

Does every water heater have the same anode rod?

No.

Anode material, configuration, access, and replacement procedures vary by water heater.

Some systems may use:

• Magnesium anodes
• Aluminum or aluminum-zinc anodes
• Powered anodes
• Multiple rods

Inspection may also require significant clearance above the water heater and enough force to remove a rod that has been installed for years.

For many homeowners, anode inspection is better handled during professional water heater maintenance rather than as a casual DIY task.

The condition of the anode rod can be especially important if your goal is extending the life of a tank-style water heater.

Check the Temperature and Pressure Relief Valve

Tank water heaters include a temperature and pressure relief valve, commonly called a T&P valve.

It is an important safety component.

The valve is designed to release water if temperature or pressure inside the tank rises to unsafe levels.

Visually inspect the valve and discharge pipe for:

• Corrosion
• Constant dripping
• Mineral buildup
• A damaged discharge pipe
• Signs the valve has recently released water

A T&P valve that continually drips should not simply be plugged, capped, or ignored.

The valve itself may be failing, but excessive system pressure or another condition could also be responsible.

Some manufacturers recommend periodically testing the valve according to specific instructions. Because an older valve may not reseal properly once operated, follow the manufacturer’s procedure or have the valve checked during professional maintenance if you are uncertain.

Never block or disable a temperature and pressure relief valve.

Look at the Expansion Tank, If You Have One

Some plumbing systems include a thermal expansion tank near the water heater.

As water heats, it expands.

In a closed plumbing system, an expansion tank provides space for that additional volume and helps control pressure changes.

A failed or waterlogged expansion tank can contribute to pressure problems that affect:

• Water heater components
• Fixtures
• Valves
• Supply lines
• T&P valve operation

If the expansion tank is leaking, heavily corroded, or no longer functioning correctly, it should be evaluated.

Checking its charge and condition is generally part of a broader plumbing or water-heater assessment rather than something every homeowner needs to perform routinely.

Inspect for Corrosion Before It Becomes a Leak

Corrosion deserves attention even when no active water leak is visible.

Check areas such as:

• Hot and cold water connections
• Shutoff valves
• Dielectric fittings
• Drain valve
• T&P valve
• Tank seams
• Connections to expansion tanks

White, green, blue, or reddish deposits around fittings can indicate ongoing moisture or corrosion.

Do not assume a dry mineral crust means the problem has stopped.

It may be evidence of a very slow leak that evaporates before enough water accumulates to form a puddle.

Catching these conditions early may allow a fitting or valve to be repaired before surrounding components are damaged.

Maintain the Area Around a Gas Water Heater

Gas water heaters require combustion air and a safe path for exhaust gases to leave the home.

Keep the area around the appliance clear.

Avoid storing combustible materials next to the unit, and do not pile boxes, cleaning supplies, laundry, or other items around combustion-air openings.

Visually inspect the venting for obvious issues such as:

• Loose connections
• Visible corrosion
• Disconnected vent sections
• Damage
• Improperly supported vent pipe

Do not modify combustion venting yourself unless you are qualified to do so.

Problems with combustion or venting can create carbon monoxide hazards, making this an area where professional inspection is especially important.

If you ever suspect a gas leak or combustion problem, stop using the appliance and follow the appropriate emergency procedure rather than continuing maintenance.

Tankless Water Heater Maintenance Is Different

Tankless systems do not store a large volume of hot water, so sediment at the bottom of a tank is not the primary concern.

Mineral scale is.

As water moves through the heat exchanger and is heated rapidly, calcium and other minerals can accumulate on internal surfaces.

That scale can interfere with heat transfer and water flow.

Over time, a tankless water heater may:

• Take longer to heat water
• Produce inconsistent temperatures
• Lose flow capacity
• Display error codes
• Become noisier
• Use more energy to provide the same hot-water output

Tankless maintenance should focus heavily on controlling scale and keeping the water and combustion paths operating correctly.

Descale a Tankless Water Heater as Needed

Tankless water heaters may require periodic descaling or flushing with a manufacturer-approved solution.

The purpose is to remove mineral buildup from the heat exchanger.

How often this is needed depends heavily on:

• Water hardness
• Hot-water use
• Equipment design
• Manufacturer recommendations
• Whether the home uses water treatment

Homes with very hard water may need tankless descaling more frequently than homes with softer water.

This is one maintenance task where the owner’s manual matters.

Tankless systems use different isolation valves, flushing procedures, materials, and service requirements. Follow the manufacturer’s instructions rather than assuming one universal flushing process applies to every unit.

If the service valves are not installed correctly or you are unfamiliar with isolating the appliance, professional maintenance is the safer option.

Clean or Inspect Tankless Water Filters

Many tankless water heaters include an inlet filter or screen designed to catch debris before it enters the unit.

If that filter becomes clogged, water flow through the heater may decrease.

Depending on the system, homeowners may be able to clean the inlet filter according to the manufacturer’s instructions.

Before removing anything:

• Shut off the appliance as directed
• Isolate the water supply if required
• Allow hot components to cool
• Follow the manufacturer’s procedure

If the unit frequently collects debris, there may also be a water-quality or plumbing issue worth investigating.

Keep Tankless Intake and Exhaust Openings Clear

Gas tankless water heaters typically use dedicated intake and exhaust venting.

Those openings need to remain clear.

Inspect exterior terminations periodically for:

• Leaves
• Debris
• Insect nests
• Snow or ice
• Vegetation
• Other obstructions

Do not modify the vent termination or install screens, covers, or other materials unless they are specifically approved for the system.

Restricted intake or exhaust can interfere with combustion and may cause the unit to shut down or operate improperly.

Pay Attention to Changes in Hot-Water Performance

Maintenance is not only a list of scheduled tasks.

Changes in how the water heater behaves can be early warning signs.

Watch for:

• Hot water running out faster
• Water taking longer to heat
• Inconsistent temperature
• Reduced hot-water pressure
• Unusual noises
• Discolored hot water
• Error codes
• Repeated burner or ignition problems
• Unexpected changes in utility use

A gradual decline is easy to overlook because homeowners adapt to it.

If showers have slowly become shorter or the water heater takes much longer to recover than it used to, something may have changed even if the system technically still works.

A Practical Water Heater Maintenance Schedule

You do not need to inspect every component every month.

A simpler approach is to divide maintenance by frequency.

Regular homeowner checks

Every few months, take a quick look around the system.

Check for:

• Leaks
• Corrosion
• Unusual sounds
• Changes in water temperature
• Moisture around fittings
• Error codes on tankless equipment
• Obstructions around gas equipment

This takes very little time and can catch developing problems early.

About once a year

Depending on the system and manufacturer recommendations, annual maintenance may include:

• Tank flushing
• Tankless descaling
• Drain inspection
• T&P valve evaluation
• Anode rod assessment
• Burner inspection
• Venting inspection
• Electrical connection checks
• Tankless filter cleaning
• Expansion tank evaluation
• Overall performance testing

Not every item needs to be performed every year on every water heater.

The system type, water quality, equipment age, and manufacturer’s maintenance schedule should determine what is actually necessary.

What Maintenance Can Homeowners Safely Do?

Most homeowners can reasonably handle basic observation and simple upkeep.

That may include:

• Looking for leaks
• Monitoring temperature
• Keeping the area around the heater clear
• Checking exterior tankless vents for obstruction
• Replacing or cleaning accessible filters when the manufacturer allows it
• Watching for corrosion
• Listening for unusual noises
• Following manufacturer-approved flushing procedures if comfortable doing so

Tasks become less DIY-friendly when they involve:

• Gas controls
• Combustion testing
• Electrical components
• Anode rods that are difficult to access
• Pressurized components
• T&P valve problems
• Significant corrosion
• Internal leaks
• Tankless disassembly
• Venting repairs

Knowing when not to disassemble something is part of good maintenance.

When Should You Have a Water Heater Professionally Serviced?

Professional service makes sense when maintenance requires more than basic inspection or when the system is already showing signs of a problem.

Have the water heater evaluated if:

• Water is leaking from the tank or unit
• The T&P valve continually releases water
• Hot water has become inconsistent
• The system makes loud popping or rumbling noises
• Rust or corrosion is spreading
• The burner is not operating normally
• A tankless unit repeatedly displays error codes
• Hot-water flow has declined
• The system repeatedly shuts down
• You are unsure when the water heater was last serviced
• The equipment is older and has had little preventive maintenance

A licensed plumber can also look at the water heater as part of the larger plumbing system.

Pressure, water quality, expansion control, piping, and installation conditions can all affect how long the equipment lasts. If those broader issues are involved, comprehensive plumbing service may be more useful than addressing the water heater in isolation.

Can Maintenance Really Make a Water Heater Last Longer?

Maintenance can improve the conditions the equipment operates under.

That matters.

Removing sediment reduces unnecessary buildup inside a tank. Maintaining an anode rod helps protect the tank from corrosion. Descaling a tankless heat exchanger helps preserve heat transfer. Addressing leaks and pressure problems can reduce stress on valves and connections.

None of those steps can reverse an already corroded tank or restore a failed heat exchanger.

That is why timing matters.

Preventive maintenance is most valuable before the system is showing serious deterioration.

When Maintenance Is No Longer Enough

There is a point where maintaining an aging water heater stops making financial sense.

Warning signs include:

• Tank corrosion
• Water leaking through the tank body
• Repeated repairs
• Major component failure
• Persistent rusty hot water
• Declining capacity
• Frequent tankless error codes
• Increasing repair costs

A leaking storage tank generally cannot be repaired in the same way a leaking valve or fitting can.

Once the tank itself has failed, replacement is usually the solution.

If an older system begins requiring repeated service, consider the total cost and reliability of keeping it rather than evaluating each repair independently.

Frequently Asked Questions About Water Heater Maintenance

How often should a water heater be maintained?

Many water heaters benefit from at least an annual maintenance review, but the correct schedule depends on the type of heater, water hardness, usage, equipment age, and manufacturer recommendations. Tankless systems in hard-water areas may need more frequent descaling.

Do water heaters really need to be flushed?

Tank-style water heaters can accumulate sediment over time. Flushing can help remove that buildup before it begins significantly affecting heat transfer, capacity, or system operation.

What happens if you never flush a water heater?

Sediment can continue collecting at the bottom of the tank. Heavy buildup may contribute to noise, reduced heating performance, longer recovery times, and additional stress on the equipment.

Does a tankless water heater need maintenance?

Yes. Tankless systems avoid storage-tank sediment, but mineral scale can accumulate inside the heat exchanger. Periodic descaling, filter inspection, vent checks, and system evaluation may be required.

How often should a tankless water heater be descaled?

The appropriate interval depends largely on water hardness, system use, and manufacturer guidance. Homes with hard water may require more frequent descaling than homes with softer water.

What temperature should a water heater be set to?

Around 120°F is commonly used in residential settings to balance hot-water needs with energy use and scald risk, but the appropriate setting can vary. Follow equipment guidance and consider household-specific needs.

What is the anode rod in a water heater?

The anode rod is a component inside many tank water heaters designed to corrode preferentially so the steel tank is better protected from corrosion. Once the rod is substantially depleted, the tank becomes more vulnerable.

How do I know if my water heater needs service?

Leaks, corrosion, inconsistent water temperature, reduced hot-water capacity, unusual noises, repeated error codes, slow recovery, or unexpected changes in performance are all good reasons to have the system inspected.

Good Water Heater Maintenance Is Mostly About Catching Problems Early

The best time to think about your water heater is not when there is already water spreading across the floor.

A quick leak check, appropriate temperature setting, periodic flushing or descaling, and attention to corrosion can tell you a lot about the condition of the system.

For tank water heaters, focus on sediment, the anode rod, drainage, pressure, and corrosion.

For tankless systems, pay closer attention to mineral scale, inlet filters, venting, and manufacturer-required service.

And for either system, take changes seriously.

A new noise, small leak, longer recovery time, or change in water temperature may be the first sign that something is beginning to fail. Catching that change early gives you more options—and is usually far less disruptive than discovering the problem after the hot water stops completely.