Water Heater Leaking? What to Do Right Now

Finding water around the water heater is stressful, and the first question is always the same: how urgent is this? The honest answer is that it depends on where the leak is and how fast it is. Here is what to do first, then how to read what you are seeing.

Step 1: Make it safe and stop the water

• Shut the cold-water supply valve on the pipe going into the top of the heater. This stops the tank refilling.
• Turn off the energy source. On a gas heater, turn the gas control to "off" or "pilot". On an electric heater, switch off its breaker. Never run an electric heater with the tank empty.
• Smell gas? Leave now and call the gas company from outside — see gas leak warning signs.
• Protect the area: a bucket or towels under a slow drip, and move stored items off a wet garage floor.

Water in the tank is hot enough to scald. Don't try to drain it or loosen fittings until it has cooled and you know what you are dealing with.

Step 2: Find where it is coming from

Dry everything with towels, then watch for where fresh water first appears.

Leaking from the top

Often the most fixable. Common sources are the water connections, a loose or corroded fitting, the temperature and pressure (T&P) relief valve threads, or the anode rod port. A top leak on an otherwise healthy tank is frequently a repair rather than a replacement.

Water coming out of the relief valve or its pipe

The T&P valve is a safety device that opens when temperature or pressure gets too high. Occasional drips can mean the valve itself is worn; steady discharge can mean the tank is actually overheating or the house pressure is too high. Don't cap or plug a relief valve — it exists to prevent a dangerous failure. Have it checked, along with the thermostat and household water pressure.

Leaking from the drain valve

The valve near the bottom of the tank can drip if it wasn't closed fully after flushing or if its washer has worn. Usually a straightforward fix.

Leaking from the bottom of the tank itself

This is the one nobody wants. If water is coming from underneath the tank and not from a fitting or valve, the inner tank has usually corroded through. Tanks cannot be patched. It is a replacement, and the leak will usually get worse, not better — so the water should stay off until it is swapped.

Condensation, not a leak

A newly filled tank, or a gas heater on a cold morning, can produce condensation that drips onto the burner area and looks like a leak. If the water stops once the tank is up to temperature, that may be all it is.

Is it time to replace?

Age matters. A tank near or past the end of its normal service life that starts leaking is usually a replacement even if the leak is at a fitting, because the next failure is rarely far behind. Our guide to water heater lifespan covers how to judge that, and gas vs. electric replacement covers the choice if it comes to it.

Is it an emergency?

A fast leak, a leak from the bottom of the tank, water spreading toward finished flooring, or any smell of gas — yes, call now. A slow drip from a fitting with the water shut off can usually wait until a normal appointment.

Call (209) 860-5004 any hour, or see water heater repair in Torrance and emergency water heater repair.

Reviewed by the Rush Plumber team — licensed, insured plumbers serving Torrance, CA and the South Bay, 3610 Torrance Blvd, Torrance, CA 90503. Call (209) 860-5004, 24/7.