Here's how to replace an old shower faucet and adjust the water temperature to prevent scalding
Even if you’re not very experienced with bath or plumbing projects, many of the steps necessary for replacing an old or damaged shower faucet are relatively simple. This project guide will show you how to quickly remove an old shower faucet and install a new one.
Tip: Block the shower drain with a cloth to prevent small parts from falling into the opening, and place a blanket or piece of cardboard on the floor of your tub or shower base to protect against dropped tools.
WHAT YOU NEED FOR THIS PROJECT
• Turn off the water supply.
• Unless you happen to have a separate cutoff valve installed in the bathroom, shut off the water to the whole house.
• Open up a faucet at a lower level in your home to relieve pressure in the lines and leave it open as you work.
Tip: To protect the finish, wrap a cloth around the connection first, and hold the shower pipe with your other hand to keep it from turning inside the wall.
• Take off the showerhead by turning the connecting nut counterclockwise with a pair of pliers.
• Faucet handles can be removed in different ways. Some have a cover plate, which can be pried off with a small screwdriver. Others, like the one featured in this video, have a small set screw somewhere on the handle. Once it’s loosened with an allen wrench, you can remove the handle gaining access to the parts below.
• The remaining components of the handle either unscrew or pull off. Keep removing parts until you reach the valve in the wall. If you have a tub spout, this will either remove with a set screw, or will twist off by turning it counterclockwise.
Plumbing inside the wall is configured for the type of shower faucet you have. Hot water typically comes in from the left, cold from the right. The two are mixed in the valve and will either go up to the showerhead, or down to a tub spout. A diverter directs which way the water goes.
• To put in a new valve, you’ll first need to remove the old one from inside your shower.
• To gain access, cut out a section of drywall approximately a foot square on the other side of the wall from your shower valve.
• To locate the valve, drill a pilot hole or two from the bathroom side next to the valve with a long bit.
• Measure an even square on the back wall, and cut the section out with a drywall saw. Save the piece to reinstall later.
• The valve is mounted to a stringer running between the studs.
• Cut the copper pipe with a tubing cutter. Cut the pipe going up to the shower, as well as the hot and cold lines below.
• Once the pipe is cut, use a reciprocating saw to take out the stringer with the old valve still attached.
• Make sure you purchase the correct valve for the faucet you’re planning to install in your shower. It should have two inlet channels for the hot and cold water, and two outlet channels for the tub spout and showerhead. Each of these fittings connects to your pipe either through male threads on the outside or female solder ports on the inside.
• If your bathroom has either a tub or shower only, then the second outlet channel will need to be capped off in the installation. Shower-only valves are also available for bathrooms without a tub.
• The valve itself must come out the correct distance from the wall, and is mounted to a stringer, which is a brace running between the studs.
• Allow for the depth of the valve, the water-resistant drywall, and the thickness of the tile or shower enclosure when setting the proper depth for the stringer. The instructions that come with the valve will show the correct dimensions for the valve and its plumbing.
• To connect to the valve, attach female adapters to the ends of the copper pipe. To ensure a leak-free connection, fittings should be soldered using a torch and lead-free solder. This process is also called sweating the pipes.
• Use a deburring tool to clean up the ends of the pipe. Insert it over the end and rotate it around several times until the section is shiny.
• Use the wire brush to clean the inside of the fitting.
• Apply a light coating of solder paste or flux to the inside of the valve fittings, and to the cleaned end of the copper pipe. Insert the end of the pipe all the way into the adapter.
• Use a torch to heat up the middle of the fitting. Apply solder to the joint between the pipes, letting it melt into the seam all the way around. Don’t overdo it – the flux will dissolve oxides and draw the solder into the seam.
• If you are interested in making the connection without using a torch, solderless connectors can be used. Simply push on and lock.
• You must use the special tools indicated on the manufacturer’s packaging to release the compression fitting.
• When using solderless connectors, make sure to thoroughly clean the ends of each pipe, and allow 7/8 inch for the connector to overlap each side of the pipe. If you’re making connections to the threaded fittings, make sure you apply a layer of Teflon tape to the threads before installing.
• Use the old valve section as a guide for assembling your new one.
• Measure and cut sections of pipe to fit the new valve.
• Since heating up the valve could damage internal components if done incorrectly, we recommend soldering female adapters to the ends of the copper pipe. These will be cut and attached to the threaded outlets of the valve.
• The remaining connections can be made with either soldering or push and lock connectors. These will be elbows for the hot and cold valves and couplings for the straight sections of pipe. Remember, there are different ways to make the plumbing connections, so choose the method you feel most comfortable with.
• You may be able to re-use the old tub spout pipe for the installation. Make sure all the plumbing is connected properly before proceeding to the next step.
• The new valve must be set to the correct depth in the wall for the faucet to install properly. It should account for the thickness of the drywall, as well as the tile or shower enclosure on your walls. Most valves come with instructions or a guide to help you get the dimensions right. The valve is mounted to a stringer, which is a cross piece support in the wall.
• In most bathroom installations, the stringer would be set to the proper depth first, and the valve will be mounted to it. But since we’re replacing a faucet in an existing bathroom, we’ll need to install our supports from the opposite side.
• Your shower valve may work differently than the one featured in this video, so consult the manufacturer's instructions before proceeding. Before beginning the test, cap off the showerhead and tub spout connections if you have them.
• If it’s not already installed, screw the test cap onto the valve, and tighten down the bonnet nut holding it on.
• Have someone turn the water back on while you check all the connections to make sure there are no leaks.
• If you don’t see any leaks, turn the water back off, remove the caps and patch up the wall.
• Each shower faucet will have specific installation instructions, so follow the directions in your owner’s manual. Some valves come with a cartridge already installed. If yours does, you can skip this step. Other manufacturers include the cartridge as part of the faucet you purchase, and it needs to be installed into the valve first.
• To install the cartridge for this faucet, make sure it’s positioned correctly according to the manufacturer’s instructions.
• Push it firmly into the valve making sure the marks on the cartridge line up with the slots on the valve. When inserted properly it should have a snug fit.
• Screw on the bonnet nut and tighten it down with pliers.
Tip: Your tub spout may install differently, so consult your owner’s manual for the correct installation instructions.
• To install the tub spout, solder the enclosed adapter to the outlet pipe.
• Apply a layer of flux to the outside of the surface.
• Remove the O-ring and any other components that could be damaged from the heat then slide the adapter over the pipe.
• Use a torch to heat up the adapter, and apply a small bead of solder to the outside seam.
• Place a piece of cardboard inside the tub to catch any drips. After it cools, place the O-ring back on and screw the tub spout onto the adapter by turning it clockwise.
• All showerheads install basically the same way, simply by screwing the nut onto the threads of the shower arm.
• The unit featured in this video has a handshower built into the showerhead, so there’s an additional step involved.
• Before installing, wrap some Teflon tape clockwise around the threads of the arm.
• Screw the showerhead onto the threads until it’s tight.
• Attach one end of the hose to the handshower.
• Add Teflon tape to the handshower connection on the showerhead, and screw on the other end of the hose.
• Not all faucet connections require Teflon tape, so check the manufacturer's instructions before proceeding.
• Snap the handshower into the cradle or any other mount that comes with the unit.
• For the shower handle, there will be some type of sleeve that slides over top of the cartridge and valve. Make sure to include any O-ring and spacer that’s called for in the installation.
• The escutcheon goes around the sleeve against the wall, and is held in place by screws.
• To prevent scalding, set the outlet temperature on your shower no higher than 120 degrees.
• Turn on the water supply and make sure there are no leaks, then slip on the handle and turn the water to the hottest position.
• Test the temperature, then turn off the water and remove the handle to gain access to the temperature limit stop. This is usually a ring or clip that’s pried up, turned either clockwise or counterclockwise according to the needed adjustment, and then reinsert the ring or clip.
• Follow your faucet’s instructions and check after each adjustment until you reach the desired maximum temperature.
• Attach the handle by tightening the set screw with an allen wrench.