How to Fix a Toilet Flush Valve: An Easy Step-By-Step Guide
If you hear your toilet running constantly, chances are you have a leaking flush valve. This is the most common problem in a toilet tank setup and is fairly easy to fix. Fixing it yourself can save a lot of money in water usage, and you won't have to hire a professional plumber.
Parts of a Toilet
- Flush valve: The mechanism inside the toilet tank that regulates the refilling of the tank after each flush. It connects to a water source through a hose or a small pipe that attaches to the bottom of the toilet tank.
- Ball float: The plastic ball that regulates water level.
- Flapper: The flat circle that seals the flush valve seat.
- Flush valve seat: The hole at the bottom of the tank.
- Flush lever: The handle that connects to the lift rod from the outside.
- Overflow pipe: The vertical pipe in the centre of the tank.
- Refill valve: The ballcock.
Types of Toilet Tank Setups and Reasons They May Leak
There are two common types of flush valves in toilet tanks. The modern ones have a cylindrical float that moves up and down a shaft in a vertical fashion, while the older models have a tank ball float at the end of a long metal rod. Much like the cylindrical float, the ball float rises and falls with the water level in the tank. When the flush lever is pulled, it lifts the flapper, allowing the water in the tank to flush down into the toilet bowl. The cylindrical float or ball float then raises with the water level, shutting off the water supply once the correct level is reached.
When there is a leak from your toilet tank, it could be any of the following reasons:
- The flush valve is damaged.
- The flush valve doesn't seal tightly because of built-up mineral deposits.
- The flapper is worn out.
To confirm a leak, simply turn off the tank's water supply, mark the water level, and wait about 30 minutes. Iif the water level has dropped, you have a leaking valve.
A small leak may seem unimportant, but if ignored, it will raise your utility bills and could even damage your flooring. It only costs about $8–$10 to fix it yourself, so follow the steps below before calling a plumber.
How to Install a New Flush Valve
If you've established that the cause of the leak is a damaged flush valve, you have to buy a new one. Take the damaged one to the store with you to make sure you are replacing it with the same model. Also, make sure that the new one has a vacuum breaker to prevent your water supply from being contaminated.
- A wrench
- A flat-blade screwdriver
- A dry towel
To fix a one-piece flush valve that has the float and flapper integrated into the valve assembly, follow these steps:
Step 1: Turn off the Water Supply
Turn off the water supply to the tank completely. Depending on how it is set up, the knob can be found on the wall behind the toilet, or by the side of the tank on a small metal pipe leading into the floor. Use your hand or an adjustable wrench to turn the knob clockwise until the water stops running inside the tank.
Step 2: Flush and Get Rid of Excess Water
Flush what is left in the toilet bowl. Because the water supply is turned off, it should not refill again. Use a dry towel or sponge to suck up whatever water is left.
Step 3: Unscrew the Flush Valve
Unscrew the two rubber bolts by the sides of the flush valve using a screwdriver. Hold the nuts beneath the bowl with a wrench as you unscrew the bolts. Note: Do not force the bolts as it may cause the tank to crack or even break.
Step 4: Replace the Flush Valve
Take out the old flush valve and insert the new one into the tank opening so that the overflow pipe is facing the flush valve. Once you have it in place, hold the valve and tighten the screws using a wrench.
Step 5: Reconnect the Water Supply and Check for Leaks
Finally, reconnect and turn on the water supply. The tank should fill, allowing you to adjust the water level. Flush and check for leaks, then tighten any nuts as needed.
What to Do If Your Tank Has a Ball Float
Follow steps one and two above, then do the following:
- Remove the ball float using a plastic snap.
- Unscrew the nut or snap the rod out of the valve.
- Put the flush valve through the hole in the bottom of the tank.
- Hold the flush valve in place with a nylon nut. The nut should be snug, but be careful not to overtighten it.
Other Causes of a Leaky Toilet
The flapper needs to be replaced if it looks warped or otherwise worn out. This is a super simple fix.
- Remove the old or worn out flapper from the overflow tube and detach the chain from the handle arm.
- Attach the new flapper to the overflow tube and hook the chain back on the handle arm.
Blockage in the Flush Valve Seat
If the flapper is in good condition and the tank is still leaking, the flapper may not be sealing against the flush valve seat due to mineral deposits.
- Check for mineral deposits on the flush valve seat.
- Clean the flush valve seat with an abrasive sponge. Don’t use anything that might roughen or scratch the surface, you just want to remove the built-up deposits.