A water heater leak usually comes from one of four places: a loose or corroded pipe connection on top, the drain valve at the bottom, the temperature and pressure (T&P) relief valve, or the tank itself. Leaks at fittings and valves are often repairable; water coming from the tank body means the heater needs replacing.
What to do right now
- Turn off the energy: switch off the breaker for an electric heater, or set a gas heater to “off” or “pilot.”
- Turn off the water: close the cold water valve on the pipe entering the top of the tank.
- Contain the water: make sure the drain pan, if present, is draining; use towels or a wet vac.
- Find where it’s coming from using the guide below, then call a plumber.
Where is the leak coming from?
| Location | Likely cause | Usually |
|---|---|---|
| Top of the tank, pipe connections | Loose fittings, corroded nipples or a failing supply connector | Repairable |
| T&P relief valve or its discharge pipe | Excess temperature or pressure, or a worn valve | Needs diagnosis; don’t plug it |
| Drain valve near the bottom | Valve not fully closed or a worn valve | Repairable |
| Under the tank, from the body | Internal tank corrosion | Replace the heater |
| Puddle but tank is dry | Condensation or a nearby pipe, AC or appliance | Check other sources |
Why the T&P valve matters
The temperature and pressure relief valve is a safety device that opens if the tank gets too hot or the pressure gets too high. If it’s dripping or discharging, the cause could be the valve itself, an incorrect thermostat setting, or high water pressure, sometimes because a thermal expansion tank is missing or failed. Never cap or plug the valve or its discharge line. Have a plumber diagnose it.
Why tanks eventually leak
Steel tanks are protected inside by a glass lining and a sacrificial anode rod that corrodes instead of the tank. Once the anode is used up, the tank itself starts to corrode. Sediment buildup at the bottom, common where water carries minerals, adds stress. When the tank wall rusts through, there’s no reliable repair.
Repair or replace?
If the leak is at a fitting, the drain valve or a replaceable valve, a plumber can usually fix it as a water heater repair. If the tank is leaking, or the heater is old and has needed several repairs, replacement makes more sense. Our water heater installation page compares tank, tankless and heat pump options.
Condos and closet water heaters
Many Boca Raton condos and villas have the water heater in an interior closet. A leak there can damage flooring quickly and reach the unit below. Drain pans, leak sensors and automatic shut-off valves reduce the risk, and many associations require some of these. If yours doesn’t have them, ask the plumber about adding them.
Leaking heater? Call (561) 794-0131 to connect with an independent plumber who handles water heater and plumbing services in Boca Raton.
Frequently asked questions
Is a leaking water heater dangerous?
The leak itself mainly risks water damage, but problems with the relief valve or gas supply need prompt attention. Turn off the energy and water to the heater and call a plumber.
Can I still use my water heater if it’s leaking?
It’s best not to. Turn it off and close the cold water supply to limit damage until it’s inspected.
Why is water coming out of the pipe on the side of my water heater?
That pipe is usually the T&P relief valve discharge. It can indicate excess temperature or pressure or a failing valve, and should be checked by a plumber.
Can a leaking tank be patched?
No reliable repair exists for a corroded tank body. Replacement is the standard fix.