Water Heater Leaking: Causes and What to Do

Likely causes, most common first

1. Leak from the tank body or the bottom: the steel has corroded through. Replacement is the fix.
2. Drip from the drain valve at the bottom: the valve may need replacing.
3. Water at the top: loose or failed fittings on the hot or cold pipes.
4. T&P relief valve or its discharge pipe dripping: pressure is high, or the valve has failed.
5. Leak at an element flange or gasket on an electric unit.
6. Condensation on the tank or pipes, which can look like a leak but stops when the unit is not heating.

What you can safely check

1. Close the cold-water valve on the pipe feeding the heater.
2. Electric unit: turn off the breaker. Gas unit: turn the gas control to OFF if you can reach it safely.
3. Dry the area and watch where new water appears first.
4. Check whether the water is coming from a pipe, a valve or the tank.
5. Move anything valuable away from the water.

What not to do

• Do not plug, cap or block the relief valve or its discharge pipe.
• Do not leave an electric heater on if the tank is draining or empty.
• Do not touch electric parts or wiring while standing in water.
• Do not assume a slow drip will stay slow.

When to call a professional

Call right away for a steady leak, any water near electrical parts, or water from the tank body. Call soon for a drip at a valve or fitting. We repair valves and fittings, and replace tanks that cannot be repaired.

Related service: emergency water heater repair.