If washbasin faucet is used for a years, water leakage may occur, which not only wastes water resources but also increases water bills. Fixing a leaking sink faucet with single handle is usually easier than you think. With the right tools and parts, you can repair the faucet in minutes even without any plumbing experience. If you do it yourself, you can save the cost of a plumber and stop annoying leaks in less than an hour.

The first thing to do is locate the source of the leak. If the water outlet drips, it means that the internal valve is not completely closed and the faucet cartridge needs to be replaced. If the leak is near the bottom of the faucet or under the faucet, it may be due to the faucet itself or other sources. Before disassembling the faucet, it is important to find out where the water is leaking, because different leaks will be repaired in different ways.

Please note that there are different types of internal valves for bathroom faucets, such as cartridge, rotary ball and ceramic discs. Compares with other types of faucet valves, ceramic discs valves are less likely leaky and usually has longer life time. Most of bathroom faucets internal valves can be disassembled and repaired using the same basic steps.

Alternative Repairs for Single-Handle Faucets

If water leaking at the base of the faucet, please check if the water flows down from the outlet to the bottom. This may be caused by a loose or malfunctioning aerator, or even a small pinhole on the water outlet. If everything looks good and it is not that the faucet outlet leaking, the fixing nut under the dome cover may be loose. Remove the faucet handle and dome cover and check to make sure the nut is tight.

A faulty cartridge is also the cause of a dripping faucet. The solution is the same for this type of leakage: change the cartridge. If water comes out under the sink or counter, it may be caused by a variety of problems, including loose or malfunctioning water supply or water supply nuts.

It is possible that the rubber or plastic gasket under the faucet is broken or malfunctioning, causing water leakage that forms a puddle on the edge of the counter or sink. To solve this problem, you need to remove the faucet and replace the gasket or seal it with plumber's putty before reinstalling. For homeowners who do not like to work with plumbing, this may require a plumber to repair the leak.

How To Change a Bathroom Faucet Cartridge

Step1: Turn Off the Water Supply

Firstly turn off the hot and cold water valves under the bathroom sink. Then turn on the faucet to release the pressure and remove any water that may remain in the water pipe and faucet. If you cannot completely turn off the water or there is no shut-off valve under the faucet, you can turn off the main water shutoff in your home.

Step 2: Remove the Faucet Handle

Finding the screw to remove the faucet handle is not an easy job. It is usually hidden under a small cover on the back or at the front of the faucet handle. Use a small flat-head screwdriver to pry up this cover from the edge; uncover it and you will find the fixing screws. Use an Allen wrench or Phillips screwdriver (if applicable) to loosen the fixing screws. On most faucets, the handle can be pulled down by loosening (rather than removing) the fixing screw.

Step 3: Remove the Collar and Retaining Nut

After the faucet handle is removed, you’ll find the retaining nut that holds the cartridge in place. Some faucets have a decorative collar or cap over the retaining nut. If your faucet has a collar, turn it counterclockwise by hand to remove it. You can use an adjustable wrench or tongue-and-groove pliers to remove the collar if it is tight. Be sure to place the wrench or pliers over the knurls or place a towel over the collar before turning to avoid scratching or damaging the finish. Then, remove the retaining nut by turning counterclockwise with an adjustable wrench.

Step 4: Remove the Faucet Cartridge

Some faucets cartridges may be held in place with a clip. (Moen is one brand that uses them.) You can remove the clip by pulling with a pair of tongue-and-groove or needle-nose pliers. Once the clip is removed or if your faucet doesn't have a clip, lift the cartridge straight up from the faucet to remove it. If it is difficult to remove, you can pull it with a pair of pliers or with a specialty tool called a cartridge puller.

If you are not familiar with water pipes or faucets, it is easy to forget what part goes where, even if you just disassembled it five minutes ago. To avoid this problem and the need to ask help for a plumber to put your one-handle faucet back in place, please take a video of yourself taking apart the faucet (or just take pictures along the way) to help keep track of each part. This is a simple method that can avoid a lot of trouble.

Step 5: Find a Replacement Cartridge

Most faucet cartridges can be found at hardware stores and home centers. Make sure you bring the old cartridge with you to be sure you buy the correct replacement, or have it ready on your phone before you head into the maze that is the home improvement store. Most faucet brand names can be found somewhere on the faucet.

If you also know the model number, most faucet manufacturer websites offer repair documents and parts information to help you find the correct cartridge. If you know the brand but not the model, brands such as Delta offer an online product identification tool to help you find your faucet and its replacement parts.

Step 6: Replace the Cartridge

Set the new cartridge in the faucet. If the cartridge had a retainer clip, install it. You may need to use needle-nose pliers to install the clip. Replace the retaining nut by turning it clockwise and gently tighten it with an adjustable wrench. Set the collar back on and turn clockwise, tightening gently with an adjustable wrench or pliers. Set the handle back on and tighten the setscrew.

Step 7: Turn On the Water

Check to make sure the faucet is in the off position and then turn on the water valves under the sink. Run the water for several seconds, checking for leaks. Then, turn it off and check to make sure the bathroom sink faucet is no longer dripping.