Water heating is one of the foundations of modern home comfort. Today’s tanked water heaters are built for dependable performance, but even small issues can undermine how well they work. Industry experts recommend annual maintenance to keep operating costs low and prevent most malfunctions. If you do run into trouble, scheduling a professional repair is the safest route. Here are the most common tanked water heater problems and how a plumber may resolve them.
Running Out of Hot Water Fast
For newer water heaters, running out of hot water may point to incorrect sizing or installation. If your system has worked fine in the past, consider whether your household usage has changed—adding just one more person can make a big difference. Lack of maintenance is another likely culprit. Over time, minerals and limescale settle at the bottom of the tank, creating sediment that interferes with heating.
Other mechanical problems can also cause short hot water cycles. A malfunctioning thermostat may need recalibration or replacement. A broken dip tube lets cold water reach the top of the tank too soon, lowering your water temperature. Faulty heating elements or a failing heat exchanger can also limit performance and usually need replacement by a plumber.
Low Hot Water Pressure
Tired of washing your hands under a trickle of hot water? Or trying to shower only to feel a weak, disappointing stream? If your cold water pressure is fine but your hot water is barely flowing at multiple faucets, your water heater is likely to blame. Common culprits include a partially closed shutoff valve, a faulty pressure-reducing valve, or sediment buildup inside the tank. These issues can sap the pressure and flow of hot water. A skilled plumber can flush the tank, adjust valves, or replace worn components to get your showers and faucets back to full strength.
Water Too Hot or Not Hot Enough
When water temperatures fluctuate, the dip tube is often to blame. This component directs incoming cold water to the bottom of the tank; if it clogs or fails, cold water lingers at the top, mixing with hot water. Temperature swings can also point to thermostat problems, a failing heating element, or issues with the heat exchanger.
If the water is consistently too hot or too cold, start with the thermostat setting. If that looks correct, the problem may involve the same mechanical issues that cause temperature fluctuations.
Rising Energy Usage
An unexplained rise in energy use can be one of the first signs of water heater trouble. That’s why it’s smart to track your monthly and annual consumption. Sediment buildup is a common driver of higher bills because it insulates the heating element, forcing it to work harder. A plumber can flush the tank to restore efficiency.
Worn or inadequate insulation can also increase energy use. At a minimum, hot water lines should be insulated. If your water heater is older, the issue may simply be age—units lose performance near the end of their service life.
Leaks
Before you start worrying about a leak, make sure the water isn’t from condensation. Depending on the season and location, light moisture on the tank can be normal. True leaks require closer inspection. Leaks from valves or connections are usually straightforward fixes, often solved by tightening or replacing a washer or valve. If the tank itself is leaking, repair is rarely practical. In most cases, replacement is the more cost-effective and reliable choice.
Discolored Hot Water
Tank water heaters use sacrificial anode rods to draw corrosion away from the tank. When these rods deteriorate, rust can seep into the water and turn it reddish. If the tank is older, it may be the tank itself that’s corroding. Sediment buildup can also discolor water, producing shades from light brown to deep red. A plumber can test, flush, or replace components to address the issue.
Unpleasant Smelling Hot Water
If only the hot water smells unpleasant—often like rotten eggs or sulfur—it usually points to bacteria inside the tank. This is common if the water heater sits unused for a while, such as after a vacation. Sometimes running hot water clears it, but a persistent smell often means the anode rod has failed. Severe bacterial buildup may require a full flush and sanitization before the tank is refilled.
Kettling and Other Unexpected Noises
A high-pitched whistling or popping sound, known as kettling, often signals high pressure inside the tank. The cause may be a faulty temperature and pressure relief valve, hard water, or sediment buildup.
Not all noises are cause for alarm. A light hum or buzz near the tank is typically normal. But banging or knocking can mean a water hammer caused by sudden pressure changes. Sediment buildup can also create gurgling, crackling, hissing, ticking, sizzling, or screeching noises—all signs that the tank needs cleaning.
Tripped Circuit Breaker
A single tripped breaker may not be a major concern, but repeated trips signal a problem. For tanked water heaters, this can be caused by bad wiring, a loose connection, or a failing heating element. Sometimes the breaker itself is worn or overloaded. Because electricity and water can be dangerous, these repairs should always be handled by a licensed professional.
Discolored Pilot Light
For gas-fired tanked water heaters, a healthy pilot light burns mostly blue, with perhaps a touch of yellow at the tip. A yellow or orange flame typically indicates an incorrect fuel–to–air mixture. Flames that appear red, green, or another color often indicate that foreign materials are burning in the combustion chamber, such as dust, oil, or carbon deposits. Cleaning and adjusting the pilot and burner components is best done by a professional to ensure safe operation.
Pilot Light Keeps Going Out or Is Hard to Relight
A pilot light that flickers, goes out, or won’t relight typically points to inadequate ventilation, a clogged pilot tube, low gas pressure, or a malfunctioning thermocouple. All of these require professional inspection and repair to ensure safe operation.
Reliable Tanked Water Heater Services in Milwaukie
3 Mountains Home Services has been serving homeowners and businesses in Milwaukie, OR, and the surrounding communities for more than 25 years. Our skilled HVAC technicians handle everything from furnaces and boilers to heat pumps, air conditioners, ductless mini-splits, and air purification systems.
We also employ licensed electricians who perform inspections, repairs, and installations for electrical panels, surge protection, indoor and outdoor lighting, EV chargers, and smart thermostats. Our licensed plumbers handle water, gas, and sewer line work, including camera inspections, drain cleaning, excavation, and trenchless repairs. We also install and service kitchen and bathroom fixtures, tanked and tankless water heaters, sump pumps, and water filtration systems.
Contact us today with questions or to schedule an appointment for water heater service.