The 11 Most Common Water Heater Problems And How To Fix Them

Your water heater works hard every day, supplying hot water for showers, laundry, dishes, and cleaning. Over time, that demand leads to wear, leaks, noise, and even system failures.

Many people don’t notice anything is wrong until they’re suddenly out of hot water. Small issues, when ignored, can grow into costly repairs. Spotting water heater problems early helps avoid long-term damage and rising utility bills.

No Hot Water at All

Turning on a tap and getting cold water is one of the most common complaints. For electric heaters, this usually means a tripped breaker or a failed heating element. Gas models may have an extinguished pilot light or a malfunctioning gas valve.

Check the breaker box first. If everything looks normal, inspect the thermostat and heating elements. Gas units may need the pilot light re-lit or the valve inspected. If you smell gas, contact a technician immediately.

Not Enough Hot Water

Getting hot water that fades fast often points to a thermostat set too low or a failed element in an electric unit. In gas systems, sediment inside the tank can reduce the space for heated water or slow down heating.

Try flushing the tank to remove sediment. Adjust the thermostat to about 120°F. If the problem continues, a faulty element or burner could be the cause.

Water Is Too Hot

Scalding water is not just uncomfortable. It can be dangerous, especially for kids or older adults. An overheated tank also increases pressure, which can lead to leaks or even tank rupture.

Check the thermostat. Sometimes it gets bumped accidentally. Keep it between 120°F and 125°F. If it is already at that setting and still too hot, the thermostat might be stuck or malfunctioning. Replacing it is often simple but must be done carefully with the power off.

Water Leaking from the Tank

Leaks are a serious concern with any water heater. A small drip can slowly flood a basement or utility closet. Leaks usually come from a failed T&P valve, loose fittings, or corrosion at the base of the tank.

Start by tightening any loose connections at the cold water inlet or hot outlet. If the temperature and pressure relief valve is leaking, test and replace it. If the leak is coming from the tank itself, especially near the base, the entire unit likely needs to be replaced.

Strange Noises from the Tank

Popping, banging, or rumbling sounds are often caused by sediment buildup inside the tank. As sediment hardens, it traps water underneath. When that water heats up, it makes loud popping noises as it escapes.

These sounds do not always signal danger, but they do signal wear. They reduce efficiency and shorten the lifespan of the tank.

Turn off the heater and flush the tank completely. If the sound returns after flushing, the buildup may be too solid. In that case, a professional may need to inspect the tank for damage or recommend replacement.

Discolored or Rusty Water

When hot water turns yellow, brown, or reddish, it is often more than just a cosmetic issue. The discoloration usually points to rust or corrosion, either inside the water heater tank or somewhere in the home’s plumbing system.

It is most common in older tanks where internal components begin to break down over time. If the water only looks discolored when the hot tap runs, the issue likely starts in the heater.

A good first step is to flush the tank. Sediment and rust can collect at the bottom over the years, especially if the anode rod has started to fail. The anode rod is a long metal piece inside the tank designed to attract minerals and rust, protecting the rest of the unit. If it wears out or becomes too coated, corrosion begins to spread to the tank itself.

If flushing the tank doesn’t solve the issue, check the anode rod. If it’s worn down or heavily corroded, replacement is likely needed. But if both hot and cold taps show discoloration, the cause may lie in aging iron pipes rather than the heater itself. In that case, it’s best to contact a licensed plumber for inspection and repair.

Foul-Smelling Hot Water

Hot water that smells like sulfur or rotten eggs is unpleasant and often surprising. That smell typically comes from bacteria reacting with the anode rod inside your tank. It is more common in homes that use well water, which can carry more natural bacteria than treated municipal sources. The bacteria are harmless, but the smell can make it feel like something is seriously wrong.

Start by draining the tank completely, then disinfect it using a safe mix of hydrogen peroxide and water. This helps eliminate bacteria that may be causing odor inside the tank or piping. Always turn off the gas or electricity beforehand, and follow your unit’s manufacturer instructions when draining and cleaning the system.

Once cleaned, consider replacing the standard anode rod with an aluminum-zinc version. This type of rod is better at resisting the chemical reaction that causes the sulfur smell. If the odor keeps coming back, you might also need a whole-house water filtration system to treat the water before it enters the heater.

Pilot Light Keeps Going Out (Gas Models)

A pilot light that won’t stay lit may point to more than a simple annoyance. It often signals an issue with one of the heater’s safety components, such as the thermocouple, pilot line, or gas control valve. These parts work together to maintain safe operation. If any of them fail or become dirty, the gas supply shuts off automatically.

Begin with the thermocouple. This small sensor sits beside the pilot flame and detects heat. If it’s dirty or misaligned, it may stop sending the signal needed to keep gas flowing. Gently clean the surface with fine sandpaper or replace it if damaged. Be sure the flame makes direct contact with the thermocouple tip.

If that doesn’t fix the issue, check the pilot line for obstructions. Dirt, corrosion, or dust can block gas flow. Lastly, inspect the gas control valve. A faulty valve may not open or close as needed. Take caution when working with gas appliances, and if you ever smell gas or feel uncertain, call a professional immediately. Safety always comes first.

Low Water Pressure from Hot Taps

When hot water pressure drops while cold water pressure stays normal, the likely cause is inside the water heater. Mineral buildup or a damaged dip tube can restrict flow.

Check the dip tube for signs of wear or cracks. Replace it if necessary. Flush the system and examine the hot water lines for blockages. In older homes, galvanized steel pipes may have hardened buildup that restricts flow and requires replacement.

Water Takes Too Long to Reheat

If your water heater seems to take forever to recover after one or two showers, there may be an issue with the thermostat, burner, or size of the unit. This is a common frustration in homes with high hot water demand or aging systems.

In electric heaters, a malfunctioning lower element can cause this. For gas models, it might be a dirty burner or venting problem. Undersized tanks can also run out of hot water quickly and recover too slowly.

Start by checking the thermostat. If it is working properly, test both heating elements in electric models. If only one is active, the recovery rate will drop by half. Clean any sediment inside the tank. For gas units, inspect the burner for dirt, rust, or debris.

Make sure the venting system is clear and working. If none of these solves the problem, your water heater might simply be too small for your household’s needs.

Water Heater Is Too Old

Water heaters do not last forever. A typical tank-style heater lasts around 8 to 12 years. After that, the risk of leaks, inefficiency, and part failures rises sharply. You might start seeing rust-colored water, inconsistent temperatures, or higher energy bills. You may also hear more noise from the tank as sediment continues to harden.

Many homeowners wait until a full failure happens. But older systems become more expensive to maintain with each passing year.

Look at the unit’s serial number or installation tag to find the age. If your heater is past 10 years old and showing signs of wear, it is time to consider replacement. A newer model will perform more efficiently and reliably. Modern units often include better insulation, improved recovery rates, and upgraded safety features. Tankless models may be a good fit for homes that want continuous hot water and better energy performance.

Let Us Handle Your Water Heater Problems

At Water Heaters Now, we deal with these water heater problems every day. We do not just fix the symptoms; we help you find the right long-term solution. From fast replacements to tankless upgrades, we handle the work cleanly, professionally, and on your schedule.