What is a pressure regulator (PRV)?
A pressure regulator valve (PRV) is a device installed on the main water line that automatically reduces incoming municipal water pressure to a safe range for household pipes and appliances, typically 40-80 PSI.
Municipal water systems in the Columbia area deliver water at pressures ranging from 60 to over 100 PSI. A pressure regulator valve (PRV) sits on your main water line where it enters the house and automatically reduces that pressure to a safe range for residential plumbing, typically between 40 and 80 PSI. Most homes need one, especially on city water systems.
Without a PRV, excessively high pressure damages fixtures faster, strains pipe joints, and stresses water heaters and appliances. The valve uses an internal spring and diaphragm to sense incoming pressure and adjusts a gate or piston to maintain the target pressure downstream. It requires no electricity and operates passively.
A failing PRV shows clear warning signs. You might notice water pressure that is inconsistent from room to room, unusually high pressure at fixtures, banging or hammering sounds in pipes (water hammer), or leaking from the relief valve outlet. Some PRVs have a test/bleed port that dribbles water continuously when the valve wears out. If you suspect a problem, a plumber can test your current pressure with a gauge and determine whether adjustment or replacement is needed. Leak detection and repair specialists can identify pressure-related damage and water losses before they become costly.