The Importance of a Water Heater Pressure Relief Valve

Different types of water heaters contain different parts. Gas-powered water heaters, for instance, have burners, whereas electric-powered water heaters have heating elements. Most water heaters, however, also have a pressure relief valve. It’s an essential safety component for nearly all traditional, tank-based water heaters as well as some tankless water heaters. What is a pressure relief valve exactly, and why is it important?

What Is a Pressure Relief Valve?

A pressure relief valve is a safety component that’s designed to relieve excess pressure. Water heaters generate pressure due to thermal expansion. As the temperature of water increases, it will expand.

The water inside of a water heater can get pretty hot. Depending on the type of water heater, as well as the settings, it may heat water to a temperature of 120 to 170 degrees Fahrenheit. Due to thermal expansion, pressure will build up inside of the water heater. Fortunately, the pressure relief valve will regulate the amount of pressure.

Why Your Water Heater Needs a Pressure Relief Valve

Without a pressure relief valve, pressure may build up inside of your water heater to dangerous levels. All water heaters generate pressure. It’s a byproduct of thermal expansion. When water becomes warmer, it expands. And because water heaters are closed, pressure will build up inside of them.

A faulty or nonexistent pressure relief valve means that pressure may build up inside of your water. When left unchecked, the excess pressure may cause your water heater to rupture. Rupturing, of course, can prove dangerous. Water heaters can explode when they rupture, especially when triggered by pressure buildup.

Pressure relief valves can leak when they fail as well. Under normal circumstances, the pressure relief valve should open automatically once the temperature of the water reached a specific temperature. If the pressure relief valve has failed, though, it may remain stuck open. It will continue to release water – even before the water has reached the specified temperature.

Repairing a Faulty Pressure Relief Valve

If your water heater has a faulty pressure relief valve, don’t hesitate to get it repaired. It may only require a new seal. A leaking pressure relief valve, for instance, may be the result of a worn seal. Replacing the seal will then stop it from leaking.

If the pressure relief valve itself has failed, you may need to get it replaced. Most pressure relief valves can be replaced without replacing the entire water heater.