Welcome to part four of our Leak Inspection and Repair Blog Series that explores bathroom leaking causes and solutions. This article focuses on how to repair shower valve leaking for two- or three-handle fixtures.

Is your shower head or handle dripping even after you turn the water off? Or perhaps your hot water peters out even though it’s on full blast? 

The culprit could be a leaking shower valve. And it won’t get better if you don’t address the issue, which often means more than simply changing a shower head. The sooner you get to the bottom of the problem and replace old or worn-out parts, the more likely you are to prevent water damage to your home.

To avoid costly repairs, investigate the source of your bathtub leaking as soon as possible. If you’re certain it’s coming from your two- or three-handle shower valve, continue reading for our quick and easy repair tips. If you have a one-handle valve that’s leaking, look out for our Fix-It Guide for One-Handle Fixtures: Leaking Shower Valve (One-Handle Moen Fixtures).  

What’s Causing My Shower Valve Leaking?

The first step to addressing shower valve leaking is to figure out what’s causing the leak. The most frequent culprits are old or worn-out parts in the existing shower valve, including the:

• Shower valve seat located inside the wall
• O-ring connected to the shower valve
• Threads inside the shower valve

The good news is that it’s a fairly simple process to remove the entire shower valve apparatus and replace these parts. 

Items Needed to Fix Your Shower Valve

To get started with your shower valve leaking repair, you’ll need the following tools and materials:

• Pocket knife/utility knife
• Phillips head screwdriver or Allen Key
• Pliers
• Flashlight
• Tub/shower valve socket wrench (if necessary)
• Specialty faucet handle remover (if necessary)
• CLR (Calcium Lime and Rust Remover) (optional)
• Seat wrench
• Teflon tape or pipe thread sealant

Preparing to Eliminate Shower Valve Leaking

Once you have your basic materials together, take a moment to prepare yourself before beginning your repair:

• First, determine whether it’s the hot or cold water valve that’s leaking. It’s easy to test: Put your hand underneath the dripping faucet to see whether the leaking water is warm or cold.  If the water is warm, your hot water shower valve is most likely your issue, and if the water is cold, the cold water valve is probably the cause of the leak. (It is possible that both hot and cold shower valves need to be fixed and even the shower diverter if you have a three-handle shower faucet.) 

• Once you’ve determined which shower valve should be replaced and assembled your tools and parts, place a towel inside the tub to protect the bottom of your tub. Cover the drain to avoid parts falling down the drain.

• Turn off your main bathroom water source. If you have an accessible shut off valve for your bathtub, shower, or bathroom use that. Otherwise find your emergency water shut off valve and shut off water to your entire home.

• Next, open up the faucet to release any water pressure that’s still in the pipes. Now you’re ready to get started.

5-Step Guide to Fix Shower Valve Leaking

Step 1: Expose the inner workings of the shower valve 

 Remove the shower handles

• Look for any screws affixing the handles to the rest of the assembly. Often the screws are hidden, in which case they’re likely under the little circular plastic or metal coverings on the center of your faucet handles. (They’re often marked with “H” for Hot and “C” for Cold).
• Pick at the seam of the covering with a utility or pocket knife until the covering pops off. Look inside to see the exposed screws.
• Insert a screwdriver into the exposed handle and turn counterclockwise to loosen the screw. It helps to gently pull the faucet handle toward you with one hand as you use the other to unscrew. (If the screw is really stuck, a specialty faucet handle remover from a local hardware store should do the trick.)

Remove the decorative cover plates

• Now that the handle is off, you’ll need to take off the decorative cover plate (i.e., escutcheons) along with the sleeve that’s covering the shower valve stem or cartridge.
• Check to see if the cover plate is attached with screws on the neck of the faucet. If so, remove the screws. The decorative pieces should come right off, exposing the cartridge.
• If there are no screws visible, the cover plates are most likely friction fitted to the wall, and you should be able to remove them by turning them counterclockwise. This can usually be accomplished by hand (without the use of pliers). You may need to score the perimeter of the cover plates or decorative faceplate in order to break the caulked seal. Simply run a utility knife around the perimeter.
• If the cover plates aren’t budging, you’ll need to use pliers. Place a rag over the cover plate first to protect it from getting scratched. Then use the pliers to turn counterclockwise.

Step 2: Remove shower valve stem from the wall

With the cover off and the valve stem now exposed, you can disengage the entire fixture from the wall.

• First, locate the nut at the base of the valve stem. Sometimes this nut is exposed and sticking out and can be easily loosened and removed with a crescent wrench. Other times, however, the shower valve nut is buried behind the bath or shower wall and will require a specialty tub socket wrench and a pair of pliers.
• Either with the crescent wrench or with the tub socket wrench, twist the nut until it loosens. The entire stem assembly should come out of the wall. 

Step 3: Replace old or worn-out valve stem parts and shower valve seat

• As you look at the shower valve stem in your hand, you may notice a worn-out O-ring at the base, the part that sat closest to the wall. The O-ring provides the seal against the valve seat, and if it is worn out, you have found at least one of the sources of your shower valve leaking. Simply screw on a replacement O-ring to easily solve that problem.
• Keep in mind a worn-out O-ring may not be the only reason for your shower valve leaking. To be safe, you should also replace the shower valve seat, the part of the shower faucet inside the wall.
• To replace the seat, you must first remove it from the wall. This requires a specialty seat wrench (which is essentially a tapered allen wrench) to remove the seat from inside the wall.
• Turn the seat wrench counterclockwise to remove the small brass seat buried in the wall. 
• Screw in the replacement seat in a similar fashion as you removed the old seat. Place the new seat on the end of the seat wrench with the threads facing out, towards the wall.
• Coat the threads with pipe thread sealant or Teflon tape to ensure a tight fit when you screw the new seat into the wall. Reinstall the seat, being careful not to let it fall off the wrench into the wall. Screw it in nice and snug, as tight as you can. 
• Another cause of shower valve leaking is worn-out threads in the shower valve stem itself. To test for worn-out threads, hold the valve stem in one hand and tug back and forth on the faucet handle to see if there’s any wiggle. If it does wiggle, that’s a clear sign your threads are worn out and you should replace the entire shower valve stem. 

Step 4: Reinstall the shower valve stem and handles

Now that the seat is replaced, you’re ready to reattach your existing valve stem (if there was no wiggle) or a new valve stem (if a wiggle indicated the threads are worn out). 

• Screw the valve stem into the valve seat by hand, then snugly tighten its nut back into place with the specialty tub socket wrench or the crescent wrench you used to remove it and a pair of pliers.
• Replace the decorative cover plate (i.e., escutcheon) back onto the valve stem the same way you removed it, either by screwing it back in place or friction-fitting it back on by turning it by hand clockwise. 
• Place the shower handle into its spot, then insert the screw into the middle of the handle. Use the screwdriver to tighten it back into place.
• Insert the decorative piece that covers the screw (if applicable). 
• Finally, use regular acrylic caulk to seal the edge where the cover plate (i.e., escutcheon) meets the shower wall to ensure that there’s no water seepage. 

Step 5: Repeat as necessary for the hot, cold, and/or diverter shower stems

If you’re in need of more thorough leak detection in Montgomery County or are looking for a reliable plumber in Germantown, MD or the surrounding areas, contact Heil Plumbing today.

Look out for more articles from our Leak Inspection and Repair Blog Series, which overview:

• Part 1 – 4 Main Causes of Pesky Bathtub Leaking
• Part 2 – Bathtub drain leaking (waste drain repair)
• Part 3 – Bathtub overflow drain leak repair
• Part 4 – You’re here.
• Part 5 – Leaking shower valve repair (for one-handle Moen fixtures)
• Part 6 – Adjusting Your Trip-lever Drain Stopper – ​​Why Your ​​Tub Doesn’t Hold Water

---

Heil Plumbing is a family-run company owned by a third-generation master plumber. We can help you with a full range of plumbing services, including toilet installation and repair, leak detection and pipe repair, faucet repair and installation, drain cleaning, and water heater repair in Montgomery County and the surrounding areas.