What is a Pressure Regulating Valve (PRV)?

Ask any plumber and they will tell you that having high water pressure is like a problem just waiting to happen. Those banging noises you hear when you turn off your faucet? That’s called “water hammer” and this is just one of the symptoms of high water pressure that creates repeated stress on your plumbing system.  Not only is high water pressure a leading cause of pipe leaks and appliance failures, but it also decreases the lifespan of all of the elements of your plumbing system including showerheads, toilets, dishwashers, and hot water heaters.  

Each of your fixtures, appliances and pipes are manufactured to handle a certain level of water pressure, usually from 60-80 psi (pounds per square inch). If they are subjected to a higher pressure they can fail and cause leaks over time. But sometimes city and local water providers pump water at levels higher than 100 psi in order to reach homes that are at longer distances or at higher elevations.  

This is where a pressure regulating valve (PRV) comes in: PRVs are bell-shaped devices located on the main water supply line where the water enters the home, near the shutoff valve. PRVs regulate the pressure in a home and keep it at a safe, steady level. They can be set to a specific pressure and adjusted if necessary. Phyn provides you with real-time information on your water pressure and you can use these readings to adjust your PRV, if necessary.

 

 

How high water pressure can affect your plumbing:

Pipe leaks

Similar to how healthy blood pressure is crucial to your overall physical health, having a safe water pressure is critical to your pipes’ health. Constant stress of high water pressure wears out pipe joints over time andl you could end up with small pinhole leaks that go unnoticed. 

High pressure also causes water hammer, which happens when fast moving water is suddenly stopped by something like a faucet turning off. When pressure is higher, the water hammer effect is magnified. With a PRV water hammer can be better controlled. 

Water heaters

Water heater leaks and bursts are a very common occurance. Typically this is caused by higher than necessary water pressure.  Water expands as it heats up. Most water heaters have what is called an “expansion tank” that is meant to offload this expansion of water. In homes with high pressure your hot water tank may have too much water because the pressure is forcing more water than necessary into it. When the water expands from getting hot it has nowhere to go. Resulting in leaks and tank bursts. 

Washing machines, dishwashers and other water-using appliances

If you look in the user manuals of most water-using appliances they are built to withstand water pressure no higher than 80 psi. Higher pressure will put appliances under constant stress and can wear them out faster. The worst possible scenario is that the water pressure can cause the inlet hose of an appliance to crack or become separated, which will cause damaging leaks and floods – ruining your floors and cabinets. 

Toilets  

Toilets and other plumbing fixtures are also designed to handle a pressure of around 80 psi. High water pressure can wear out the flushing mechanism of the toilet tank and it can turn a simple toilet flapper leak into a costly water waster as more water rushes into the tank faster causing it to fill and refill constantly. 

 

How do I know if I have a PRV?

If you know where your water shut off valve is located, you can look for your PRV. It is typically within a few feet of this shutoff and it looks like a bell. 

 

Will Phyn work if I don’t have a PRV?

If you don’t have a Pressure Regulating Valve (PRV), you will be able to monitor your water pressure in real-time from the Phyn app and perform manual Plumbing Checks to proactively check for leaks. However, Phyn will require a much longer timeframe to become accurate. 

During the time that Phyn improves in homes without PRVs you may experience more frequent “false alerts”.   Phyn’s ability to accurately show you the water use of the different fixtures in your home will also be limited.  As always, the more feedback you provide to Phyn by labeling and verifying the fixtures being used in your home, the faster it will improve its accuracy. 

 

Why does Phyn work better if I have a PRV?

Aside from the many plumbing benefits to having a PRV to keep your water pressure stable, PRVs filters out and “quiet” the noise from upstream pipes in the street and in your neighborhood. It’s like closing the door to a noisy street so you can hear the conversation inside.  Like any of us, Phyn “hears” better in a quieter environment.

This pressure “plot” below shows how Phyn sees a water “event” such as a toilet flushing or a faucet being used in a home with a PRV. You can clearly see the beginning and end of the event and that the pressure spikes have distinct characteristics.                  

 

And here is the pressure signature of a water use without a PRV.  The beginning and end are not clearly defined and the jagged edges created by pressure “noise” make it difficult for Phyn to recognize the subtle characteristics that can tell it this was a normal use or a potential leak. 

 

 

How Much Does a PRV Cost?

PRVs can cost as little as $50. Having one installed by a professional plumbing will take a few hours. The cost of plumbing work can vary by plumber and location.  Installation often requires cutting out a small section of your main water line and soldering the ends of the regulating valve onto your pipe.  

We recommend that all homes have PRVs, not just to benefit Phyn, but because they are a great step that you can take to mitigate the risk of leaks by controlling your water pressure.