How to Replace a Toilet Fill Valve

The toilet fill valve is a mechanism inside the toilet tank that regulates the level of water in the tank. Sometimes you need to change the fill valve for different reasons. When it does not work properly, extra water might drain into the tank. As a result, water constantly runs into the overflow tube and the toilet bowl. You can easily replace the toilet fill valve yourself, saving some extra money that you pay to the plumber otherwise. 

Things You Need to Change the Toilet Fill Valve 

  • New toilet fill valve
  • Pliers or crescent wrench
  • Scissors
  • Ruler or tape measure
  • Bucket
  • Sponge
  • Cloth or rag

Step 1: Cut Off the Water Supply

Cut off the water supply with the help of the valve which is usually positioned on the lower left-hand side of the toilet or on the wall behind it. Flush the toilet in order to empty all the remaining water from the tank.

Step 2: Dry the Area

Wipe any left water with a sponge, so it does not leak onto the floor.

Step 3: Disconnect the Water Line

Disconnect the water line from the tank. Usually you can don’t need instruments, but you should use a pair of pliers if it is overly tightened.

Step 4: Remove the Fill Valve

Using a wrench, remove the retaining nut that holds the old fill valve in place. Clean the area around the hole in order to install the new valve properly. 

Step 5: Adjust the New Valve

Adjust the new valve to the appropriate height, so that the “critical level” mark on the valve top is located no less than 1 inch above the overflow tube.

Step 6: Insert the Fill Valve

Insert the new fill valve in the opening where you had removed the damaged one. Be careful when installing the rubber washers because they prevent leakage around the opening. Use a plastic nut to attach the valve and tighten it by hand, otherwise you might over-tighten it and break the tank.

Step 7: Connect the Fill Valve

Reconnect the hose for the water supply to the valve’s bottom. Use the fittings that come with the valve and tighten by hand. Inside the tank, link the attaching clip to the new refill, and fasten it to the overflow tube. Cut the tube at length and link it to the valve.Turn on water and if it leaks, re-tighten connections.

Step 8: Check for Leakages

If it does not leak, you did a perfect job and saved some money. The water in the tank should reach a level at about 1 inch below the top of overflow tube. If it goes too high or too low adjust the height keeping up with the included instructions.