Why Is My Tankless Water Heater Leaking from the Relief Valve?

Tankless water heaters are an excellent addition to any home, offering the convenience of on-demand hot water while reducing energy expenses. However, like any appliance, they may encounter occasional issues throughout their lifespan, such as leaks in the relief valve. While a tankless water heater leaking from the relief valve can cause concern, there’s no need to worry. In this blog post, we will explore the underlying reasons, provide solutions to address the problem and share valuable tips to prevent future issues.

What is the Relief Valve?

Before we get into the reasons for the leaky relief valve, it’s essential to understand what it is and how it works. The relief valve is a safety device that automatically releases water pressure from the water heater’s system when the water pressure exceeds the safe level. The valve operates by opening and closing, depending on the water system’s pressure to prevent tank rupture or explosion.

Reasons for the Leaking Relief Valve:

There are various reasons why a relief valve in a tankless water heater may leak. One of the most common reasons is overheating due to high water temperatures. If the water temperature exceeds the set limit, the relief valve opens to release the pressure, which causes a leak. Another reason could be excessive water pressure caused by a malfunctioning valve or a defective expansion tank.

How to Fix It

While fixing the leaky relief valve may not always require a professional, if your tankless water heater is still under warranty, it’s best to call the manufacturer. Otherwise, the following steps can help solve the issue: Turn off the power supply and cold water inlet to the heater. Drain the system, and then remove the relief valve from the water heater. Check for any signs of corrosion or sediment. If there is no damage, reattach it and turn the power back on.

Prevention Tips

Prevention is always better than cure, so here are some tips to avoid future relief valve leaks: Firstly, check the temperature controller and make sure it is set to the appropriate temperatures. Secondly, have a plumber inspect the pressure relief valve regularly to prevent any defects or damages. Lastly, consider installing a water pressure regulator to keep the water pressure at a stable level.

Final Thoughts

A tankless water heater leaking from the relief valve can occur due to multiple reasons, most of which can be fixed without calling a professional. It’s essential to understand the relief valve’s function and keep an eye on the water temperature and pressure. With proper maintenance and care, your tankless water heater can provide hot water for many years without any issues.