A water heater leaking a little today can empty 40 or 50 gallons onto the floor tomorrow. Take these steps first.
Shut it down
- Power or gas off. Electric: switch off the breaker. Gas: turn the control knob to off.
- Water off. Close the cold water valve on the pipe above the heater.
- Drain if it is leaking heavily. Attach a hose to the drain valve and run it to a floor drain or outside.
Find where it is leaking
- Top: a loose inlet or outlet connection or a leaking valve. Repairable.
- Side, at the relief valve: the valve is faulty or the tank is over pressure. Needs a plumber promptly.
- Bottom, at the drain valve: the valve can be replaced.
- Bottom, from under the jacket: the inner tank has rusted through. No repair is possible.
Repair or replace?
Connections and valves are a straightforward water heater repair. A leaking tank means water heater replacement, which is often completed the same day. It is also the time to consider a tankless unit.
If it is flooding
Close the main water valve to the house and call an emergency plumber.
Common questions
Can I still use the water heater if it is leaking a little?
If the leak is at a fitting, briefly, until it is repaired. If the tank itself is leaking, shut it down.
Why is my relief valve dripping?
Either the valve is worn or pressure in the tank is too high, often because an expansion tank has failed.