Your water heater is leaking: what to do in the first 10 minutes

Step 1: cut the water and the energy source

There is a cold water shut-off on the pipe entering the top of the heater. Turn it clockwise until it stops. If the valve is seized, use the main shut-off for the house, usually near the front hose bib or in a box near the sidewalk.

On a gas heater, turn the dial on the control valve to OFF. On an electric heater, switch off its breaker at the panel. Never drain a heater that still has power to the elements.

Step 2: read the leak location

Dripping from the temperature and pressure relief valve on the side usually means the valve is doing its job because pressure is too high, or the valve itself has failed. That is a repair, not a replacement.

Water at the cold or hot connection at the top is often a failed nipple or flex line. Also a repair.

Water seeping out from under the jacket, along the floor around the whole base, means the inner tank is rusted through. Tanks cannot be patched. Replacement is the only fix.

Step 3: get the water out of the garage

Attach a hose to the drain valve at the bottom and run it to the driveway. Open a hot tap somewhere in the house so the tank can vent and drain. Expect the water to be scalding for the first several minutes.

If the heater sits in an interior closet or upstairs, shop-vac the pan and check the ceiling below for staining before anything else. Water in a ceiling is a bigger bill than the heater.

How long tanks last around here

Inland Valley water is hard, and hard water shortens tank life. A standard 40 or 50 gallon tank that made it 8 to 12 years has had a normal life. Past 12 years, a leak is a signal to plan a replacement rather than chase repairs.

If you are replacing anyway, this is the moment to decide between another tank and a tankless unit, because the gas line and venting work happens once.