How to Replace a Shower Valve

hand turning on a shower after replacing the shower valve
hand turning on a shower after replacing the shower valve

A shower faucet valve controls the flow of water through the shower head, as well as the temperature of the water. The most popular type of shower valve in new homes is a pressure-balancing valve, which is designed to maintain a constant ratio of hot and cold water, reducing the risk of accidental scalding.

However, ongoing normal use over time can affect the function of the shower valve, leading to worn out seals, leaks, slow valve reactions, and temperature fluctuations. Other signs that a shower valve replacement may be needed include excessive lime scale build-up, a loose or broken shower handle, and water pressure problems.

While issues can be caused by regular wear and tear, they may also be due to hard water, worn-out seals, worn bearings, water hammering, and aggressive or improper use of the shower valve. If you have a faulty, worn, or leaking shower valve, use this guide to learn how to replace shower valve cartridges and valve assemblies.

Types of Shower Valves

There are several types of shower valves that are commonly used in new homes, including pressure balancing valves, thermostatic valves, diverter valves, and transfer valves. In older homes, you may also see a shower mixing valve, though this type is not typically used for renovations, upgrades, or new home construction.

Given that shower valves are not universal, it’s important to learn how to identify the different valve types to find the right replacement.

  • Pressure balancing valves are one of the most commonly used shower valve types. These valves are made to maintain a consistent ratio of hot and cold water when the user adjusts the shower handle to help avoid accidental scalding. Most pressure balancing valves have a single handle to control the temperature and flow of water.

  • Thermostatic valves tend to be more expensive than pressure balancing valves because the user can preset the water temperature and then simply wait for the shower to reach the ideal setting. This type of two-handle shower valve will also typically have a volume control feature, allowing the user to set the amount of water coming from each outlet.

  • Diverter valves are typically seen in bathrooms that have a tub shower combo. A shower diverter valve can redirect the flow of water through the shower head or through the tub faucet. Generally, diverter valves have a pull arm located on the bathtub faucet that can be pulled up to divert the flow of water from the tub faucet to the shower head.

  • Transfer valves are designed to allow water to flow to multiple fixtures, such as to a handheld shower head while simultaneously to the overhead rain shower head. Newer transfer valve models may even have digital controls with unique programs and features to customize the shower settings.

  • Mixing shower valves or manual shower valves are one of the older options still in use in some homes. These valves mix the cold and hot water from separate taps before the water exits the showerhead. A significant drawback to this design: If there is a drop in the cold water pressure due to a flushing toilet or a dishwasher cycle, then the user may be at risk of scalding because this type of valve doesn’t regulate sudden pressure fluctuations or temperature.

RELATED: 8 Steps You Can Take to Increase Water Pressure in Your Home

Project Overview

Working Time: 1 to 3 hours
Total Time: 2 to 4 hours
Skill Level: Intermediate
Estimated Cost: $50 to $100

Before You Begin

Don’t start a shower valve replacement or shower valve cartridge replacement before gathering the appropriate tools, parts, and replacement shower valve components. Shower valve assemblies and cartridges are not universal, so it’s necessary to determine the size and type of shower valve currently installed in order to find a suitable replacement.

If you want to change the type of shower valve, be prepared to open up the wall to cut and disconnect the existing shower valve. After cutting the pipes to remove the shower valve, you will need to solder in new fittings before installing a shower valve. If you don’t have experience with soldering, then it may be best to hire a plumber to complete this upgrade.

STEP 1: Turn off the water and cover the drain.

Start the shower valve replacement project by turning off the water to the shower. If there is an isolation valve for the shower, you can use this valve instead of shutting down the water to the whole home, but if the shower does not have an isolation valve, then you will need to use the main water valve to cut off the incoming water supply. After turning off the water, open the valve to allow any remaining water to drain.

When the shower valve is finished draining any excess water, place a towel in the bottom of the shower or tub to block the drain. This will help prevent any small tools or parts from getting stuck in the drain while you work.

STEP 2: Remove the shower handle with a hex key or screwdriver.

Removing shower handle plate with drill
Removing shower handle plate with drill

Photo: homedepot.com

The next step is to expose the shower valve by removing the shower handle. Typically, a shower handle is secured with a single set screw located at the bottom of the handle. Check the set screw to determine whether you need a hex key wrench or a screwdriver.

Loosen the set screw and remove the shower handle. Put the parts aside in a small bucket or a similar container to avoid losing any parts.

STEP 3: Remove and clean the trim plate.

Use a screwdriver to loosen the screws holding the trim plate to the shower wall. Set the screws aside, then remove the trim plate.

If you plan to reuse the current trim plate, take this opportunity to clean any dirt, caked-on debris, or any caulk that is stuck to the edges of the trim plate or the shower wall. Caulk is easy enough to remove by peeling it with a utility knife or prying it off with a set of needle-nose pliers.

STEP 4: Remove the old valve.

Removing shower valve with wrench
Removing shower valve with wrench

Photo: homedepot.com

In most cases, you can resolve any issues with the existing valve by replacing the shower valve cartridge. If you are replacing the cartridge instead of the entire shower valve assembly, then you simply need to use needle-nose pliers to pull out the valve clip, remove any retaining nuts with a hex wrench, and then pull the old valve cartridge out with groove joint pliers.

However, if you are replacing the entire shower valve assembly, then you may need to make the hole around the existing shower valve larger or open up a new hole on the other side of the wall, exposing the back of the shower valve. After the shower valve is exposed, use a pipe cutter to cut the pipe going up to the shower, as well as the hot and cold water lines.

STEP 5: Install a new valve.

Installing a new shower valve cartridge is as easy as sliding the new cartridge into the existing valve, securing any necessary retaining nuts, and inserting the valve clip to lock the cartridge in place. However, if you are replacing the entire valve assembly, the work to install the valve is significantly more difficult. For those who have no experience with soldering, it’s recommended to hire a plumber to complete this upgrade.

Avid DIYers with basic plumbing knowledge and experience soldering will need to take measurements of the existing water lines, using the new valve assembly for reference. Ideally, you will be able to solder in several copper couplings to connect the new valve to the ends of the copper pipes.

Make sure to clean the pipes and fittings, then apply flux paste to the connections. Pull out a length of solder and hold it to the base of the first fitting. Use a blow torch to heat up the pipe until the solder turns to a liquid. If done correctly, the solder should flow into the gap between the fitting and the pipe, creating a watertight seal. Repeat this process with each subsequent fitting to install the new valve.

If the plumbing lines are made of PEX piping, then you will need to use PEX adapters and a PEX crimping tool to connect the new valve assembly to the existing pipes. This is relatively easy. Simply measure and cut short lengths of PEX pipe, then use a coupling and PEX crimping tool to crimp the coupling around each connection, squeezing the pipe to create a watertight seal.

STEP 6: Turn on the water and test for leaks.

Person replacing faceplate on shower faucet
Person replacing faceplate on shower faucet

Photo: istockphoto.com

Now that the new shower valve or shower valve cartridge has been installed, turn the water on and look for any leaks. If you installed an entire valve assembly, carefully inspect each connection to ensure that the installation succeeded without any leaks.

After verifying that the new shower valve is not leaking, replace the trim plate and reinstall the shower handle. Remove the towel from the drain, then turn the shower on to test the functionality of the new shower valve.

RELATED: Solved! What to Do About a Leaking Shower Head

Final Thoughts

When replacing a shower valve, take some time to inspect the existing shower valve before purchasing a suitable replacement product for this project. To find the right product to replace the leaking shower valve, check the brand and type of shower valve currently installed.

If you can’t find any notable marking to help identify the shower faucet, you may need to take apart the faucet and measure what’s there to ensure you purchase a compatible replacement. Alternatively, you can remove the existing valve and take it to a local home improvement store to get help finding a suitable replacement product. However, the water will need to be off during this time, so make sure anyone left at home is aware that the water is supposed to remain off, or you may return to a flooded bathroom.

Shower valve replacement cost estimates can vary depending on the type of shower valve, the complexity of the project, and whether the valve cartridge will be replaced or if the entire assembly will be replaced.