Have you ever asked yourself when looking around your water heater, “What is that thing that looks like a bell?”. It is a pressure regulating valve, or PRV for short. Its purpose is to regulate the pressure in a home and keep it at a safe, steady level. The clanks and bangs you hear when turning on your water are called water hammer, and this happens when you have high water pressure in your home. If you hear these all the time and don’t have a PRV on your water line then call Royal Flush, the best plumber in Decatur, GA.