A leaking water heater pressure relief valve (PRV) is a common issue that can lead to bigger problems if not addressed promptly. This valve is a critical safety component of your water heater, designed to release excess pressure and prevent explosions or damage to the system. If you’ve noticed water leaking from this valve, it’s essential to determine the cause and take the necessary steps to fix it.

What Is a Pressure Relief Valve?

The pressure relief valve is a small but crucial device located on the side or top of your water heater. Its primary function is to release water when the tank’s pressure or temperature exceeds safe levels. This prevents excessive buildup that could lead to a dangerous situation.

Common Reasons for a Leaking PRV

1. Excessive Pressure Inside the Tank

If your water heater is experiencing high pressure (above 150 psi), the PRV will leak to relieve it. This can be caused by:

• A malfunctioning pressure regulator in your home’s plumbing system

• High water temperature settings, leading to excessive steam buildup

• A closed system, where the water heater expands without room for pressure release

2. High Water Temperature

Most water heaters should be set between 120–140°F. If the thermostat is set too high, it can cause overheating, leading to increased pressure and PRV leakage.

3. Faulty or Worn-Out Valve

Over time, the PRV can wear out or develop mineral buildup, preventing it from sealing properly. This can result in a slow but continuous leak.

4. Sediment or Debris Buildup

Hard water deposits and sediment can accumulate in the valve, preventing it from fully closing. Regular maintenance can help keep this from happening.

How to Fix a Leaking PRV

1. Check the Water Temperature

• Locate the thermostat on your water heater and ensure it is set between 120–140°F.

• If the setting is too high, lower it and monitor if the leak stops.

2. Inspect the Water Pressure

• Use a pressure gauge on a faucet to measure the home’s water pressure. It should be between 40-80 psi.

• If the pressure is too high, a plumber may need to install or replace a pressure-reducing valve (PRV) on your main water line.

3. Flush the Valve

• Turn off the power and water supply to the heater.

• Place a bucket under the PRV and lift the lever to flush out debris.

• If water continues to leak afterward, the valve may need replacement.

4. Replace the Pressure Relief Valve

If the valve is old, damaged, or continues leaking after troubleshooting, replacing it is the best solution. A licensed plumber can help ensure the installation is done correctly.

When to Call a Professional Plumber

If your PRV continues to leak despite adjusting the pressure and temperature or if you’re unsure how to handle the issue, it’s best to call a professional. A leaking PRV can be a symptom of a larger problem, such as a failing expansion tank or pressure regulator.

At Portage Plumbing Services, we specialize in diagnosing and fixing water heater issues, ensuring your system runs safely and efficiently. If you’re experiencing a leaking PRV, don’t wait—contact us today for expert assistance!