Why Is My Water Heater Leaking?

Water travels down and pools at the lowest point, so the puddle location does not always match the leak location. Dry the tank, valves, pipes and floor completely with a towel, then watch where the water reappears first. That tells you the true source.

Most leaks fall into one of four spots, and each one points to a different fix. Here is what each one means.

The temperature-and-pressure relief valve sits on the upper side of the tank with a pipe running down toward the floor. It is a safety device that opens when pressure or temperature gets too high. A steady drip usually means one of three things: the valve has worn out, the home's water pressure is too high, or the system lacks a working expansion tank to absorb heated-water expansion.

This is almost always repairable. A plumber tests the incoming water pressure, checks the expansion tank, and replaces the T&P valve if it has failed. Ignoring it is risky because the valve is your tank's pressure safety release.

The drain valve at the base of the tank is used for flushing sediment. Over time the washer inside can fail or the threads can loosen, causing a slow drip. This is a common and inexpensive repair. The valve can usually be replaced without removing the tank, though the water and power or gas must be shut off first.

Water at the top of the tank often comes from a cold inlet, hot outlet, or the flexible supply connectors. A loose connection, a worn washer, or a corroded dielectric nipple can all leak. These are repairable, but corrosion at the top fittings can be an early sign of a tank nearing the end of its life, so a technician checks the overall condition while making the repair.

If water is seeping from the steel shell, a seam, or pooling at the very base with no valve involved, the tank has corroded through from the inside. There is no safe or lasting repair for a failed tank body. The unit must be replaced, and the sooner the better, since a small leak can become a sudden rupture that floods the area.

First, shut off the water supply to the heater using the valve on the cold inlet pipe. If it is a gas heater, turn the gas control to off. If it is electric, switch off the breaker. Mop up standing water to limit damage, then call for service. If the leak is from a valve or fitting, we can often repair it the same day. If the tank has failed, we help you choose and install the right replacement quickly.