Fixing a Leaking Single-Lever Kitchen Faucet: A Comprehensive Guide

Whether you have a Schuller or Next125 kitchen faucet, a common issue that many homeowners face is a single-lever faucet leaking from below the handle after the water supply has been turned off.

Identifying the Issue

When your single-lever faucet leaks from beneath the handle despite the water supply being turned off, it typically indicates an internal problem within the faucet cartridge. This guide provides a step-by-step process to diagnose and fix the issue, with specific instructions for both Schuller and Next125 brands.

Preparation and Tools Needed

Before you start, it is essential to take the necessary steps to ensure the faucet is completely off and prepare the necessary tools:

Steps to Follow:

Step 1: Turn Off the Water Supply

Locate the water shutoff valves located under the sink and turn them off for both hot and cold water.

Step 2: Gather Necessary Tools

The following tools are required for the repair:

A flat-head screwdriver An adjustable wrench Possibly a replacement cartridge specific to your Schuller or Next125 model (consult the user manual or contact the manufacturer for the correct type).

Diagnostic and Repair Steps

Step 3: Remove the Handle

Find the set screw concealed under the handle. Use the flat-head screwdriver to loosen and remove this screw. Carefully lift the handle off the faucet stem.

Step 4: Unscrew the Retaining Nut

Below the handle, you will find a retaining nut that holds the cartridge in place. Use the adjustable wrench to loosen and remove this nut.

Step 5: Extract the Cartridge

Pull the cartridge straight out of the faucet body. In some Schuller models, you might need to rotate the handle before extracting. The cartridge contains several components such as O-rings and seals that are prone to damage and wear over time.

Step 6: Inspect the Cartridge for Damage

Thoroughly inspect the cartridge, focusing on the O-rings and seals, which are the most likely sources of leaks.

Step 7: Replace the Cartridge

Purchase a replacement cartridge that matches your faucet model. Insert the new cartridge into the faucet body, aligning it properly. Ensure that all components are in the correct position.

Step 8: Reattach the Retaining Nut

Securely tighten the retaining nut using the adjustable wrench to hold the cartridge in place.

Step 9: Reinstall the Handle

Place the handle back on the stem and tighten the set screw with the flat-head screwdriver to reattach the handle.

Step 10: Turn On the Water Supply

Gradually open the water shutoff valves under the sink to turn on the water supply. Check for any leaks. If leaks persist, ensure that the cartridge is seated correctly and retighten the retaining nut if needed.

Additional Tips for Successful Repair

Refer to your specific Schuller or Next125 faucet user manual for detailed instructions and troubleshooting tips. Take photographs of the disassembly process for easier reassembly. If you encounter any difficulties or are unsure about any step, do not hesitate to contact a qualified plumber for assistance.

By following these steps, you can resolve the issue of a single-lever kitchen faucet leaking from below the handle after the water supply has been turned off. Remember, regular maintenance and timely troubleshooting can prevent such issues and extend the lifespan of your faucet.