That persistent "drip-drip-drip" from your toilet tank doesn't have to mean an expensive plumber's visit. Replacing a faulty fill valve is simpler than most homeowners realize—even for beginners. With basic tools and about an hour, you can solve common toilet leaks and save on repair costs.

Before beginning any plumbing work, these preliminary steps ensure safety and efficiency:

• Shut off the water supply: Locate the shut-off valve behind the toilet and turn clockwise until tight.
• Drain the tank completely: Flush repeatedly until no water remains in the tank.
• Gather necessary tools: Adjustable wrench, channel-lock pliers, clean rags, and a compatible replacement fill valve (check your toilet's model number).

With preparations complete, proceed with removing the malfunctioning unit:

• Disconnect the supply line: Use an adjustable wrench to loosen the water supply connection at the valve's base.
• Remove the mounting nut: Underneath the tank, unscrew the plastic nut securing the valve to the tank.
• Extract the old valve: Gently lift the valve assembly upward through the tank opening.

Modern fill valves typically feature universal designs for straightforward installation:

• Secure the new valve: Insert the replacement unit through the tank hole and hand-tighten the mounting nut beneath.
• Reattach the supply line: Connect the water supply tube to the new valve's tailpiece, tightening with a wrench—avoid overtightening to prevent cracks.

Proper calibration ensures optimal performance:

• Restore water supply: Slowly reopen the shut-off valve while checking for leaks at all connections.
• Adjust water level: Bend the float arm or twist the adjustment screw until the water stops 1 inch below the overflow tube.
• Test functionality: Flush several times to verify proper filling and shutting-off.

While most modern fill valves follow this standardized process, some high-efficiency or specialty toilets may require manufacturer-specific instructions. Always consult included documentation for model-specific guidance.