Have you discovered water around your water heater but aren't sure where the water came from? A leak can indicate that your tank has eroded and needs replacing, but the problem is oftentimes much simpler and cheaper to fix. There are a couple of places to check for problems and potential leaks before you jump to replacing your entire unit.

Drain Valve

The drain valve is located near the bottom of the tank and is used when you need to remove water from the tank for repairs or for yearly tank flushing. A leaking drain valve is often easy to diagnose because the water will pool directly under the valve. But you can also test to make sure the drain valve is the source.

Hook a garden hose up to the drain valve. Place the remaining end of the hose over a floor drain or out a window. Insert a flat-head screwdriver in the notch on top of the drain valve and turn the screwdriver counterclockwise to open the valve. Water should start flowing out of the hose. Turn the screwdriver clockwise to shut the valve. Remove the hose and check for signs that the water flow didn't stop.

Note that it's normal for the valve to still drip a few times once it's closed, but if the drip continues or is more powerful than a drip, your unit needs a new drain valve. You can purchase a new valve at the hardware store and replace the part after you have fully drained the tank.

Temperature and Pressure Release Valve

The temperature and pressure release valve is a safety feature that ensures the water inside the heater doesn't become overly hot or overly pressurized, which can lead to burns or the potential explosion of your tank. Water can leak out of this valve during the normal course of operation. But frequent leaks out of the valve mean that either your unit is set at too high of a temperature—which means the valve is being tripped too often—or that the valve is broken and needs to be replaced.

You can check the temperature using your owner's manual to both find the unit's thermostats and to find the recommended upper temperature for the unit. If the temperature setting checks out, you can replace the valve yourself if you have a lot of appliance repair experience.

If you are a novice, call in a plumber from a service like Actionaire Inc to replace the temperature and pressure relief valve. A mistake during installation can render the valve nonfunctional and can make your unit equally nonfunctional—or, worse, make your water heater dangerous.