Water Heater Leaking? What to Do Right Now

Step one: protect your home

If water is actively leaking, start by shutting off the cold water supply valve on the pipe that runs into the top of the heater. Turn the handle clockwise until it stops. This stops new water from entering the tank. Next, turn off the energy source. On a gas heater, set the gas control to the off or pilot position. On an electric heater, switch off the breaker at the panel.

Move stored items away from the heater and use towels or a wet vacuum to collect the water. If the leak is large or the heater is in a closet or attic, call a professional right away so the tank can be drained safely. Hot water can cause burns, so let the tank cool before touching fittings.

Find where the water is coming from

Not every puddle near the heater means the tank is leaking. Look carefully at each of the common sources before assuming the worst.

• Supply connections at the top of the tank can loosen or corrode.
• The temperature and pressure relief valve can drip if it is worn or if pressure in the tank is too high.
• The drain valve near the bottom can leak if it is not fully closed or its washer has failed.
• Condensation can form on gas heaters when very cold water enters the tank.
• Water dripping from the bottom of the tank shell usually means the inner tank has corroded through.

Leaks that can usually be repaired

Leaks from fittings, the drain valve or the relief valve are often repairable. Loose connections can be resealed, a worn drain valve can be replaced, and a faulty relief valve can be swapped for a new one. If the relief valve is discharging because of high pressure, the real fix may be a pressure regulator or a thermal expansion tank on the plumbing system. A technician will test the water pressure to find out.

Because the relief valve is a critical safety device, never cap or plug it to stop a drip. It is designed to release pressure and prevent a dangerous failure.

Leaks that mean replacement

When the inner steel tank rusts through, there is no reliable repair. Water seeping from under the jacket or from the bottom of the heater is the most common sign. Rusty water from the hot taps and a tank that is more than ten years old make tank failure more likely. In that case, the safest choice is replacing the water heater before the leak gets worse.

Replacement is also a good time to consider whether a different size or a tankless unit makes sense for your household. We explain the options, and our replacement work includes seismic strapping, code updates and haul-away of the old unit. For pricing, call for a free quote.

How to prevent future leaks

Regular maintenance helps a tank last longer. Flushing sediment, checking the anode rod and testing the relief valve can catch problems early. Southern California's hard water speeds up sediment buildup, so many homes benefit from yearly service. Installing a thermal expansion tank where required also protects the tank from pressure swings.

If you are not sure how old your heater is, the serial number on the label usually includes the manufacture date. Our team can help you read it and plan ahead instead of waiting for an emergency.

Get help from a local team

The Water Heater Warehouse is based in Fullerton and handles leaking water heaters across Orange County and nearby areas. Call us with a description of where the water is coming from and how old the heater is. We will tell you what to do while you wait and send a licensed technician to repair or replace the heater.

Related service

Learn about our emergency water heater repair, or see our water heater repair in Fullerton.

Frequently asked questions