Water pressure and pressure reducing valves

Water pressure that is too high is hard on a house. It can make pipes bang, cause faucets and toilets to leak or run on, shorten the life of the water heater and appliances, and over time can contribute to leaks in the plumbing. Pressure that is too low is more noticeable, with weak showers and slow-filling tubs, and it can have several causes besides the valve.

Many homes have a pressure reducing valve (PRV), a bell-shaped brass valve near where the water line enters the house, that brings the street pressure down to a safe level for the building. Plumbing codes generally call for a PRV where street pressure goes above 80 psi, and some guidance recommends keeping household pressure at or below 60 psi. A PRV wears out. Signs include pressure that creeps up in the evening or overnight, banging pipes when a tap is shut, a dripping relief valve on the water heater, and pressure that changes suddenly.

What we do. We measure the pressure with a gauge to see what you really have, check the PRV and the pipes around it, and tell you whether the valve needs adjusting, replacing, or installing. If the PRV you have is working, we will say so. We also check whether an expansion tank is needed, because a PRV makes your plumbing a closed system, and heated water then has nowhere to expand.

Low pressure. If pressure is low at every tap, the cause may be the PRV set too low, a partly closed valve, a failing service line, or a utility issue in your area. If only one fixture is weak, the cause is usually at that fixture, such as a clogged aerator or cartridge.

What affects the cost. Whether the PRV is replaced or newly installed, how easy it is to reach, whether the piping around it needs work, and whether an expansion tank is needed. We quote after measuring.