How to Replace a Toilet Fill Valve in 8 Simple Steps

Always shut off the water supply before performing work on your toilet. There should be a water valve just below the toilet tank, between where the pipe comes out of the wall and where it connects to the toilet tank. Typically, you’ll turn the valve clockwise until it stops moving to shut it off.

After you’ve shut the water off, remove the tank lid and hold the flusher down to drain as much water as possible. Then, use a turkey baster to suck up the remaining water. You can also use a sponge or some towels to do this. Or, if you have a wet-dry vacuum, it will make quick work of the task.

Your toilet’s fill valve is typically off to one side and has a tube attached that connects to the overflow pipe. In older toilets, the float connects to the top of the fill valve. For newer models, it is the plastic column that includes the float.

Locate the nut that attaches the fill valve to the water supply line on the outside bottom of the tank. Loosen it by using a wrench or channel lock pliers and turning it counterclockwise. To prevent rotating, you may need to use a second set of pliers to grab the bottom of the fill valve from inside the tank.

Your new fill valve should include a rubber washer to prevent leaks from the base of the fill valve. Slide this onto the bottom flange of the fill valve’s tailpiece (the skinny end).

If necessary, adjust the height of your new fill valve so that it’s taller than the overflow tube but still short enough to allow the tank lid to close. See your manufacturer’s instructions for doing this, as different models have different methods.

Insert the new fill valve into place with the rubber washer at the bottom. Then, using your fingers, carefully tighten the fill valve nut connecting the supply line at the outside bottom of the tank. Do not use pliers and be careful not to overtighten, as this can crack the toilet tank or the valve.

Once everything is in place, turn your water supply back on and allow the tank to refill. Then, give it a test flush to ensure everything’s in working order.