How to Replace a Toilet Float Valve.
If your toilet is filling slowly or overfilling, it may be time for a new float valve. If you have one that still has a ball on the end of a long arm, it is defiantly time to upgrade.
Begin by shutting off the water supply. Hopefully there is a valve on the floor by the toilet. If not, you may have to cut off the water supply to the whole house. In the worst case, you may have to cut off the supply at the meter, but be aware that most utility companies don’t like you messing with their equipment.
Remove the lid form the tank and set it aside in a safe place. Open the flapper valve and drain out as much water as possible. Use a towel or two to soak up the rest of the water. Note that any water you leave in the tank will run out on the floor when you remove the old fill valve.
Unscrew the supply tube from the fill valve. An adjustable wrench or small pipe wrench should work for this task. You can usually leave the tube connected to the valve at the floor.
Unscrew the lock nut from the valve assembly. Older ones will have an actual nut while newer ones will have a plastic ring. It is OK to break the plastic if necessary to get it off. If it is stubborn and will not unscrew, use a hammer and screwdriver to tap it a few turns.
Lift the old float assembly out of the tank. Clean the area around the hole in the bottom of the tank. Make sure there is a sealing gasket or ring on the new float assembly. Slip it in the hole in the bottom of the tank and line up the rubber tube so that it can connect to the center overflow tube.
Put the hold down nut in pale and tighten it so that the valve will not move around. Reattach the water supply tube. Some new float valves have a mechanical reset to keep then from cycling excessively. If your new n has such a device, attach the chain clip to the flusher lever so that the mechanism trips when the handle is flipped.
Turn on the water and check for leaks. The tank will begin to fill. If not, check the trip on the mechanical reset device. Check the water level when the valve closes to make sure it is at the correct height marked on the back of the tank. Adjust the float if necessary.
Once the level is set, give the toilet a test flush. The tank should start to refill as soon as the water starts to drain. The little tube should direct a stream of water to the overflow to help sweep the bowl.
If the water does not flow, the reset may not be triggering properly. Adjust the chain as necessary. Once the tank refills, check for leaks again. Tighten the pipe fittings as need to correct the leaks.