Some of the first signs of a failing pressure regulator are a leaking water heater or commode. The water coming from a faucet may also exit with such force that splashing or water “hammering” may occur.
Excessive noise: If your hot water heater is rattling or emitting a high-pitched whistling noise, it's likely the sound of steam trying to escape the tank, which is a sign of far too much pressure pressing against the inner walls. This means the relief valve isn't doing its job and may need replacing.
How do I know if my pressure-reducing valve is bad? Thumping, banging, hammering, or vibrating noises in the walls… High water pressure, water leaking from faucet, toilet running constantly…
Contaminants, like dirt, lint, rust, sludge, or even the misalignment of the valve can cause the pressure relief valve to stick. At this point, you might see that your system is above pressure, or you'll notice other pressure relief valves in the system releasing to make up for this valve's malfunction.
Under normal conditions, the useful safe service life of a pressure relief valve is 10 years from the original date of manufacture. However, the safe useful life of the valve may be shortened by certain environmental conditions and other factors. At times, replacement may be necessary much sooner.
Pressure relief valve replacement costs an average of $220 between parts and labor, or anywhere from $50 to $300.
A Pressure Reducing Valve (PRV) is an Automatic Control Valve designed to reduce a higher unregulated inlet pressure to a constant, reduced downstream (outlet) pressure regardless of variations in demand and/or upstream (inlet) water pressure.
Normal water pressure is generally between 40 and 60 PSI. Most homeowners prefer something right in the middle around 50 PSI.
Four common failures associated with automatic valves are found at a high frequency in poorly performing control loops. These are Dead band, Stiction, Positioner overshoot, Incorrect valve sizing, and Nonlinear flow characteristic.
WARNING: Under normal conditions, the useful safe service life of a pressure relief valve is 10 years from the original date of manufacture. However, the safe useful life of the valve may be shortened and replacement required in less than 10 years depending on the environment in which the valve lives.
The most common valve failures are bent or broken valves due to contact with the piston or another object in its path. A burnt valve is another type of failure that happens when things go wrong in the valvetrain.
In the most basic terms, the difference is that pressure control valves are the first line of defence and is therefore used for primary safety, while pressure relief valves are used as a last resort backup since they are used to maintain a pre-set downstream pressure.
A pressure relief valve regulates pressure increases in a functioning system. A pressure safety valve rapidly reduces the system's pressure to a safe operating level.
Your water heater's relief valve can start leaking for one of two reasons: either the valve was triggered to open because of excessive temperature or pressure, or the valve itself is faulty. In the first case, the valve will drain water out of the discharge pipe as explained above.
Typically, water pressure regulators cost about $50 to $100 on average1, though you could end up paying up to $2001 depending on the size of incoming water line.
Unfortunately, main water shut off valves can become clogged with mineral deposits and grit. They can be damaged to the point where they need to be replaced.
Exposure to moisture can cause the components to rust over time. Eventually, the rusting becomes so severe that the part can no longer function properly. Excessive pressure can also cause the pressure regulator to fail.
Once the valve releases the pressure, it can be reset within seconds by moving the reset handle.
If the pressure reducer will not feed enough water into the boiler to reach the desired cold-pressure setting, before messing with re-adjusting the valve's feed pressure nut and screw, consider that the internal strainer in the valve may have become clogged.
If your home receives water from the city lines, you most likely have a pressure regulator already installed. If you are uncertain whether your home has one or not, finding its location is simple. Locate the main shut-off valve of your home and look nearby. The PRV should be located directly next to the valve.