An electric hot water heater supplies hot water to a home. It heats, stores and transports water. A hot water heater is equipped with a drain valve, or pressure relief valve, to release excess water stored in the tank. A drain valve is a safety feature to ensure the tank performs to specifications and prevents pressure buildup that can result in an explosion. A number of issues can cause water to come out of an electric hot water heater drain valve.
Leaky Drain Valve
A drain valve can wear and break over time and, when it does, it's possible for the valve to leak water. In most cases, you can repair the leak by replacing the valve. However, if it's the tank that is causing the leak, not the valve, the tank needs replacing.
Tank Pressure Is Too High
The drain valve is set to release water when the tank pressure reaches a certain level. In some cases, the drain valve activates when the main water supply pressure is greater than the pressure level set on the valve. The Uniform Plumbing Code requires water companies to supply water to homes at pressures between 50 and 70 pounds per square inch (psi). If your valve is set to release water at 60 psi and water is delivered at 70 psi, it can activate the drain valve. Change the setting of your drain valve or contact the water company to confirm supply pressure to correct the problem.
Water Company Flushes Out the Water Lines
When your water supply company flushes out its water lines, it can cause water to leak from the tank through the drain valve. The company periodically flushes its lines to rid them of sediment buildup. The surge of water is sometimes too large for your tank to accommodate, causing it to release excess water from the drain valve. In general, most companies attempt to alert homeowners of a planned flush prior to it occurring, so homeowners can make arrangements to accommodate the excess water flow.
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