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Trying to perform a simple DIY or simply learn more about what happens behind your shower wall? This guide to how your shower faucet works will help you better understand how to keep your family safe in the shower and build a shower that everyone can enjoy!
One of the most frustrating things for renters or homeowners is not knowing how things in their homes work. This means when something’s not working, you have to hire a plumber to fix it, which can be costly. Not only that, but it’s also often time-consuming and frustrating. By knowing more, you’ll feel more in control and have a better idea of how much you should pay.
Enter this friendly guide! Today, we’ll explain how your shower faucet works. Whether you want to fix a leaky head or solve a hot water problem, this post can get you started. Or perhaps you want to simply swap out one shower head for another. We can tell you about that too, plus what’s going on behind your shower walls.
We’ll take a peek back there, so you can feel confident about a simple DIY. Even when you wind up hiring someone for a more complicated job, a little savvy never hurts. We’ve got your back!
Now let’s begin.
The Shower Faucet: A Genius Invention
Believe it or not, showers didn’t use to be as common as they are now. Bathing was the hygiene fix of choice, and people either bathed in public baths or in a tub.
Today, over 80% of American homes have showers, in part because of technological advances in plumbing. Also, showers have a smaller footprint than bathtubs and are therefore more practical, especially in smaller spaces
Believe it or not, showers also use less water than filling the bathtub. In fact, a typical shower uses less than 30 gallons of water. Meanwhile, a filled bathtub can use as much as 50 gallons per bath.
With Shower Faucets, Variety is the Spice of Life
People use showers all over the world, but they certainly don’t look the same.
Showers can range dramatically from outdoor contraptions to luxurious and highly advanced setups. In coastal cities, many use outdoor showers after a day at the beach to keep sand out of the house. Meanwhile, in Europe, an entire bathroom with a tiled floor, drain, and shower faucet converts into a shower.
In the U.S., standard, builder-grade showers consist of either a standalone glass-surround shower or a tub/shower combo. Either way, you’ll find the shower head mounted on the wall. Ready to peer behind that wall? Let’s do it!
The Shower Faucet: Behind the Wall
If you cut through the tile behind your shower faucet, here’s what you’ll find.
- Studs (the plumbing nestles between the extra studs that provide support for the shower walls).
- Main vent stack (usually three inches; this is part of the waste plumbing system)
- Showerhead riser (extends to shower head so that it’s higher than your head)
- Pressure-balancing valve (we’ll go into more detail on this shortly)
- Cold water supply and hot water supply (these pipes are usually ½” each)
- Drain riser pipe along with other components. These include a reducing coupling, drain line, and p-trap. (The p-trap is a two-inch pipe that extends to the drain, which is usually in the center of a standalone shower.)
Much of the plumbing behind the wall consists of copper pipe or PVC piping. The average DIY-er can do some fixes, but more complicated projects may require a plumber.
Outside of replacing a shower head, however, the most common DIY is to change out the shower valve. So, let’s dive a little deeper into this contraption.
The Shower Valve
If you’ve ever gotten scalded by hot water when somebody flushes the toilet, you have an idea of how a shower valve works. A shower valve can make your shower time more comfortable while keeping you safe.
Cold water blasting through the shower faucet can cause you to jump. If you’re a healthy, able-bodied adult, that’s fine. But small children, seniors, and disabled people may have trouble jumping out of the way.
A sudden temperature change can cause people to slip and fall in the shower. This can prove very painful or even deadly. Hot water can also cause you to jump, but more importantly, it can scald you.
A shower valve helps prevent these sudden changes in water temperature.
But Can’t I Just Adjust the Water Heater Temperature?
Some may want some alternatives to the hassle of installing a shower valve. This is a big mistake. Sure you can adjust the water heater temperature. But this means your washing machine and dishwasher may not get your clothes and dishes as clean. These appliances need higher temperatures for some cycles.And although the energy-conscious often advise recommends keeping your water temperature at 120 degrees, this can backfire. Even 120 degrees isn’t hot enough to kill some bacteria, including Legionella, which behind your shower faucet.
There are two main types of valves used to prevent scalding. These include what are known as pressure-balance valves and thermostatic valves.
One of the simplest valves is the pressure-balance valve. It controls the pressure coming through from the hot water and cold water supply pipes, but it does not detect the temperature; we’ll explain more about why this matters in a moment.
Water flowing into the pressure-balance will first encounter spring-driven gaskets referred to as check stops. These keep the water from the two different lines from invading the others’ lines, which is invaluable for properly managing the flows. You can work on the valve thanks to screws in the check stops that turn off the line you’re working on.
The pressure-balance spool is at the heart of the valve. The water pressure coming from the hot and cold lines causes a small piston to vibrate back and forth, controlling the pressure of the output.
Where a drop in the cold for water caused by, say, a toilet flush, might have resulted in only hot water reaching you, now the piston vibrates to slow the flow of hot water, keeping your water at the temperature you set the handle for.
Another component of the pressure-balance valve is the shower cartridge. A shower cartridge works because it’s connected to the handle. When you pull the handle to turn on the water and adjust the temperature, the cartridge slides forward, allow hot and cold water to mingle and flow together towards the shower head.
Finally, the temperature limit stop is a small piece of metal that is screwed into the rod of the above-mentioned cartridge. This keeps the valve from being fully opened, preventing scalding.
The downside to a pressure-balance valve connected to your shower faucet is that since temperature isn’t detected, without a properly installed temperature limit stop, the water could be as hot as possible.
The other kind of anti-scald valve you’ll find, if you’re wondering how your shower faucet works, is the thermostatic valve. Unlike the pressure-balance valve, the thermostatic valve has two handles to control the volume of the water and the temperature.
People looking to conserve energy appreciate this kind of valve because it allows you to adjust the flow while you are shampooing your hair or doing something else that doesn’t require direct water.
The wax element hidden inside is the central component to this kind of valve. The wax responds to temperature changes in the water; hot water causes it to expand and stop the hot water at the maximum temperature you set, while cold water causes it to contract.
This is a truly anti-scald device since you’ll be able to set your water heater to the recommended 140 degrees without risking burning.
Which Should I Choose?
When you’re deciding on a shower faucet to connect to your anti-scalding valve, you should think about who will be using the shower. For people who can use a single handle to adjust water, a pressure-balancing valve works great.
Thermostatic valves are more expensive but are more precise and often better options for the young or elderly.
Now that you know how your shower faucet works, you’re in a much better spot to make sure the people in your home are safe from scalding water and to be able to see to minor repairs or DIYs. Even if you plan on hiring a plumber, at least now you’ll be able to understand fully the changes he or she is making to shower!
Featured image: CC- Public Domain via PxHere.