A water heater usually leaks from a loose connection, a drain valve that is not fully closed, a relief valve releasing pressure, or a corroded tank. Turn off the power or gas, close the cold water supply valve on top, and check where the water is coming from. A leak from the tank itself means the heater needs replacing.
Key takeaways
- Leaks from fittings and valves can often be repaired.
- Water coming from the tank body or bottom usually means the tank has failed.
- Turn off power or gas and the cold water valve before anything else.
- Hard water speeds up tank corrosion in East Valley homes.
What should you do right now if your water heater is leaking?
- Turn off the energy. For an electric heater, switch off its breaker. For a gas heater, turn the gas control knob to "off".
- Shut off the water. Close the cold water inlet valve on the pipe at the top of the heater. If it will not turn, close the home's main valve.
- Protect the area. Move boxes and stored items away. In a garage, sweep water out the door. In a closet, use towels and a wet vacuum.
- Find the source. Dry everything with a towel, then watch where new water appears.
- Call the right person. A plumber repairs or replaces the heater. If water reached drywall, flooring or cabinets, a restoration provider dries that damage.
Why is my water heater leaking?
| Where the water appears | Likely cause | Usually fixable? |
|---|---|---|
| Top of the tank, at the pipes | Loose inlet or outlet fitting, or a corroded nipple | Yes, by tightening or replacing fittings |
| From the side pipe (discharge tube) | Temperature and pressure relief valve opening | Often. The valve or system pressure needs checking |
| At the drain valve near the bottom | Valve not fully closed, or a worn valve | Yes, by closing or replacing the valve |
| Under the tank, from the bottom | Corroded tank from sediment and age | No. The heater needs replacing |
| Drips inside a gas burner area | Condensation, or a leak above | Condensation is normal in small amounts |
The temperature and pressure relief valve is a safety device. If it is releasing water, the tank pressure or temperature may be too high, or the valve may be worn. Never cap or plug it. Have a plumber check it.
Is a leaking water heater dangerous?
The leak itself is mostly a water damage risk, not an explosion risk. Real danger comes from three places: a relief valve that has been blocked or tampered with, electricity near standing water, and gas leaks. Treat a heater that is hissing, rumbling loudly or releasing very hot water from the relief valve as urgent.
Why do water heaters fail sooner in Arizona?
East Valley water is hard. As the tank heats, minerals settle at the bottom as sediment. That layer makes the burner or elements work harder, causes popping and rumbling sounds, and helps the steel tank corrode from the inside. Many tank heaters last around 8 to 12 years, and hard water can shorten that.
Location adds risk. In many Apache Junction homes the heater sits in the garage, so a failure floods the garage and flows under the door into the house. In manufactured homes, the heater is often in an interior closet, where water goes straight into the subfloor. See leaks under a mobile home for what happens next.
Water heater flooded the garage or a closet? Get the water extracted before it reaches the walls.
Call: (856) 481-6893Who do you call for a leaking water heater?
Call a licensed plumber for the heater itself. Call a water damage restoration provider if water spread past the heater's pan or the garage floor, especially into drywall, carpet, baseboards or cabinets. Homeowners insurance often covers the sudden water damage from a failed tank, but not the heater. Our insurance guide explains why.
How can you prevent water heater leaks?
- Flush the tank once a year to remove sediment, following the manufacturer's steps.
- Have the anode rod checked every few years. It protects the tank from corrosion.
- Install a drain pan with a drain line, and a water leak sensor beside the heater.
- Check the area around the heater once a month for rust, drips or damp spots.
- Plan a replacement as the heater approaches the end of its life, rather than waiting for a failure.
Water heaters are one of many leak sources in a home. Our guide to signs of water damage in walls shows how to spot the others.