Toilet Slow Flush Problem Fixed

Fix a Slow Flushing Toilet with Dual Buttons.

Learn how to fix a toilet that has a slow or weak flush, especially models with two flush buttons on top of the tank. I’ll show you how to make a simple adjustment that usually solves the problem without needing to replace any parts.

What Causes a Slow Flush?

If you press the flush button and the water just swirls weakly or stops too quickly, the issue is often with how far the button can travel. When the buttons sit too low in their housing, you can’t press them down far enough to fully activate the flush mechanism inside the tank. This gives you a partial, ineffective flush every time.

The Simple Adjustment Fix

You can usually fix this in a few minutes by adjusting the mechanism inside the tank. Here’s how.

Follow these steps:

1. Remove the button cover. Gently lift or unscrew the plastic cover that holds the two flush buttons. Set it aside.
2. Take off the tank lid. Carefully lift the ceramic or plastic lid off the toilet tank and place it somewhere safe where it won’t fall.
3. Locate the adjustment screw. Inside, you’ll see the flush valve mechanism. Look for a plastic cylinder or screw in the center, right under where the buttons were. This is the adjustment screw.
4. Adjust the screw for more power.
   • To make the flush stronger, you need to lengthen the button’s travel. Turn this center screw counter-clockwise to unscrew it. You can do this with your fingers.
   • For maximum flush power, unscrew it all the way until it stops. For a medium setting, unscrew it halfway.
5. Reassemble and test. Put the tank lid back on. Place the button cover back over the mechanism, ensuring the buttons sit on top of the now-taller plastic rods. Press the buttons—they should now sit higher and feel like they can be pressed down further.
6. Test the flush. Press the large button for a full flush. It should now engage fully, releasing all the water in the tank with more force. The small button should also work more effectively for a partial flush.

How to Adjust the Water Level (Optional)

If you want more water in the tank for an even more powerful flush, you can also adjust the fill valve.

1. Find the fill valve. This is the mechanism on the left side of the tank with a float (usually a ball or cup) attached.
2. Adjust the float. Look for a screw or a clip on the fill valve.
   • To increase the water level (for a stronger flush), turn the adjustment screw counter-clockwise or lift the float arm higher.
   • To decrease the water level (to save water), turn the screw clockwise or lower the float arm.
3. Let the tank refill and check. Flush the toilet and let the tank refill. The water should stop at your new level.

When This Fix Isn’t Enough

If adjusting the screw doesn’t solve the problem, there might be a different issue, like a faulty flapper valve or a clog. Learn how to fix another common problem with our guide: Toilet Not Filling Up With Water.

A quick note on parts: Toilet mechanisms can vary. The part shown here is common in many European-style toilets. In American toilets, the fill valve is often larger and on top of the tank. Always make sure you get the right replacement part if one is needed.