If the flush valve in the toilet cistern stops working properly or if there is a leak, it may be time to replace the flush valve. Although, at first glance, it is better to entrust this plumbing work to specialists, you can independently replace the flush valve of the toilet cistern with minimal hassle by following a few simple steps.
Steps
Part 1 of 3: Preparing for Installation
Step 1. Turn off the water in the toilet cistern
Before starting the installation, shut off the water supply to the toilet cistern to prevent flooding in the toilet.
- Usually the shut-off valve is located on the water supply pipe near the wall.
- Turn off the water by turning the valve clockwise until you feel resistance.
Step 2. Empty the remaining water from the toilet cistern
Draining the remaining water from the tank will give you easy access to the interior.
- This will also prevent residual water from the cistern from leaking onto the toilet floor.
- Soak up any remaining water with a sponge and squeeze it into a bucket.
Step 3. Remove the tank
Now, inspect the bottom of the tank and find the water supply hose, disconnect it. Then, using an adjustable wrench, unscrew the nuts and bolts securing the tank to the toilet and remove the tank.
- Lift up neatly the cistern and it will detach from the toilet.
- Turn the tank upside down and place it on the toilet seat.
Step 4. Locate and disconnect the drain valve
Locate the thick tapered rubber gasket and remove it. You will see a large plastic nut under the gasket. Loosen and unscrew the plastic nut to remove the drain valve.
- Begin to loosen the nut by turning it counterclockwise with pliers.
- There will immediately be a drain valve behind it.
- Release the hose clip (looks like a paper clip) by pushing it in. This clamp connects the drain valve to the filling valve.
Step 5. Clean the surface of the drain valve area on both sides
Use 409 or similar glass cleaner and chlorine bleach to clean surfaces that come in contact with the drain valve.
- This will get rid of any dirt or residue in the drain valve seal and ensure you don't have any leaks.
- Use a rag and cleaner.
Part 2 of 3: Replacing the Valve
Step 1. Install a new valve
The new valve will be inserted in the same way as the old one was pulled out. Insert the new valve through the bottom of the tank. Take the valve with the threaded side up and slowly guide it through the opening so that your hand is in the reservoir. Be careful not to screw it on too tightly, otherwise it could damage the reservoir.
- Make sure the black tube extending from the top of the new valve is 2.5 cm below the toilet lever or handle on the left side of the toilet cistern.
- Cut the tubing to the desired height before reinstalling it. The manufacturer's instructions will indicate the required height. For example, for a Fluidmaster 507A / B / D drain valve, cut the overflow tube so that it is at least 2.5 cm below the hole in the tank where the drain arm is attached.
Step 2. Install a new rubber pad
After installing the drain valve in the hole, install a new thick rubber gasket (the same type you removed). Then, while holding the valve firmly with your hands, secure it with a new retaining nut.
Step 3. Replace the hose that is attached to the drain valve
Replace the hose and connect it to the black plastic tube extending from the top of the drain valve.
Step 4. Place the cistern back on the toilet
Turn the tank over to the correct position and carefully place it on the toilet, taking care to avoid damaging newly installed replacement parts.
- Reinstall the old nuts to secure the cistern to the toilet.
- If you have purchased a toilet cistern kit, use the new bolts that come with it.
Step 5. Connect the damper chain
Step 6. Connect the water supply hose
The water supply hose located at the bottom of the tank must be reconnected at this point to resume water supply. It has a plastic threaded nut at the end.
- Connect it to the filling valve (looks like a small white tube) by hand tightening the nut onto the threads of the tube.
- Then, using a wrench, tighten the nut a quarter turn. Do not over tighten.
Part 3 of 3: Testing and Troubleshooting
Step 1. Make sure there is no leakage in the cistern toilet
Flush the toilet a few times to check for leaks. If the toilet is leaking, it will be immediately visible.
- Look under the toilet with a flashlight and see if water is dripping.
- Determine where the leak is. Typically, water can seep through a loose connection to the supply line or through a leaky gasket.
- Shut off the water to check the tapered gasket and flow connection.
- Check and tighten connections to eliminate leakage.
Step 2. Make sure the water rises to the water mark
The water level should normally be in line with the water mark on the inside of the toilet. If the water in the cistern does not rise to the level required for the toilet, adjust the filling valve.
You can adjust the filling valve by jerking the entire valve up or down. For minor adjustments, use the filling valve adjusting screw
Step 3. Listen for the whistling noise or the sound of spontaneously flowing water
If you hear a whistling or noise similar to the sound of air coming out of a balloon, the flap valve is not closing. Adjust by slightly raising or lowering the valve. The screw for the flap valve is usually on the float, which looks like a small barrel and moves up and down with the water level.