Pressure Reducing Valve

If your home has a Pressure Reducing Valve or PRV it’s important to understand not only how it works but to also verify that it working properly. A PRV is designed to regulate water pressure to ensure that your static pressure is less than 80 psi. By code, all homes should be less than 80 psi.

The only way to check a PRV is to check your water pressure. This can be done with a simple water pressure gauge. When checking your water pressure you should let the water run for about 10 seconds to get rid of excess pressure from thermal expansion.

All PRV’s will fail over time, usually around the 15 year mark. When a PRV fail’s it will do one of three things.

  1. No longer regulate water pressure allowing the full pressure from the city into your home.
  2. Restrict your water volume causing poor water flow throughout your entire house.
  3. Restrict water from exiting your home which can cause excessive pressure from thermal expansion.

Issue #3 is the least common but can result in the biggest problem. If your Temperature and Pressure Relief valve drips on your water heater it is highly possible your PRV could be clogged.

The image on the left is a clogged return on a PRV. The image on the right you can see a small weep hole at the top portion of the inner area.

Clogged PRV Old pressure reducing valve