A leaking bathtub faucet can drive up your water bill more quickly than you may expect. While professional repairs are one option, fixing a leaking bathtub faucet is a task that is within the capabilities of virtually any homeowner. Here is a step-by-step process that you can use to fix almost any double-handle bathtub faucet leak.
Remove the Faucet Handles
Repairing a leaking bathtub faucet does not usually require removing the faucet itself. Instead, leaks are usually caused by worn-out parts inside the faucet handles, so only the handles need to be removed. Before you remove anything, the first step is to shut off your home's water intake.
Some bathtub faucet handles will have exposed screws, while others will require the handle inserts to be removed first. The inserts are round covers on the faces of the handles, usually labeled "hot" and "cold." You can pull off the inserts by wedging a flathead screwdriver or other flat tool under their edges.
When the faucet handle screws have been removed, you can pull the faucet handles off of their stems. The stems can then be removed by turning them counterclockwise and pulling them out of the wall. In some cases, you may find that the stems are too tight to turn by hand and must be unscrewed using a shower valve socket wrench.
Replace the Seat Washers
After you have removed the faucet handle stems from the wall, you should see small rubber washers on the end of each stem that was inside the wall. These are the seat washers that stop the flow of water to your faucet when the handles are turned off. The seat washers will wear down over time as the faucet handles are turned on and off, preventing them from sealing off the flow of water to your faucet.
The seat washers should have screws in their centers that keep them fastened to the faucet handle stems. Remove this screw and pry the washers off with a knife or screwdriver. You can take the seat washers to a local plumbing supply store to find the right washers to replace them with. Purchase liquid thread sealant while you are there, as you will need this for placing the stems back in the wall.
To complete this repair, first slide the new washers over the ends of the stems and replace the stem washer screws. Next, coat the threads of the stems with liquid thread sealant and screw them back into the wall. Finally, screw the faucet handles back onto the exposed ends of the stems and replace the faucet handle inserts if your handles have them.
Replace the Valve Seat
If your tub is still leaking after the seat washers have been replaced, it is likely that the valve seats are damaged. The valve seats are brass rings that the seat washers press against to shut off water flow to your faucet. The valve seats can become uneven as they wear, allowing gaps to appear between the seats and seat washers when the handles are turned off.
To repair the seats, you must disassemble your faucet handles as detailed above. Once the stems are removed, insert a faucet valve reseating tool into the wall and screw it into the stem sockets. Turn the handle on the tool three times while pushing the tool firmly into the wall to file the valve seats. You can now remove the tool, replace the faucet handles, and test for leaks. Repeat this process until your bathtub faucet is no longer leaking.
With these simple steps, you can repair a leaky bathtub faucet at minimal cost and prevent the leak from driving up your water bill. Of if you feel you cannot do this on your own, contact a plumbing repair company to help you.