Why Won't My Toilet Flush? 6 Causes and Solutions

Discover six possible reasons why the toilet won't flush

Why won't my toilet flush

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The toilet is one of the most commonly used plumbing fixtures in the home, so when the toilet doesn't flush or the flushing power is significantly reduced, it can be inconvenient. To resolve this situation, you will first need to troubleshoot the toilet flushing issues.

Toilets may not flush for various reasons, including a disconnected chain, faulty flapper, low water level, a damaged float, rim jet clogs, or simply a drain blockage that needs to be cleared with a plunger. If you are asking yourself why won't my toilet flush, then this informative guide to common toilet problems can help identify the issue and fix your flush.

Disconnected Lever

Not every toilet has a lever flush system, but if your toilet has a lever, then there is a chance that it became disconnected from the flapper. The lever is typically connected to the flapper by a loose length of chain. However, if the chain comes unhooked from the flapper or disconnects from the lever, then when you press the lever, nothing will happen.

Remove the lid of the toilet tank so that you can inspect the connection between the flush lever and the flapper. If the chain just came loose during normal operation, reattach it and test to ensure the toilet flushes. If the chain is damaged or broken entirely, then you will need to replace the chain to restore the flushing capabilities of the toilet.

In some cases, the only issue with the chain is that it is too long, so when you press the lever, it doesn't apply enough force to lift the flapper. This can be resolved by cutting the chain to a shorter length with a set of wire cutters. Just make sure that you don't cut it too short, as this could lead to the flapper not sealing properly.

Closed Inlet Valve

The toilet requires water to flush, which is why the toilet tank fills with water after each use. If you try to flush the toilet, but nothing happens, then the issue may be that the inlet valve to the toilet is closed. This can happen if the valve gets nudged accidentally during regular cleaning or it may be closed because you were completing a repair and simply forgot to open the valve. Fix this issue by opening the valve to allow water to flow into the toilet. When the tank is full, flush the toilet to ensure the issue is fixed.

If you turn the valve on and the toilet still doesn't fill, check the faucet to determine if the rest of the home has water. In some cases, the water may be turned off at the main valve for the home if you or someone else were working on the plumbing system. Alternatively, the water to the neighborhood may be shut down by municipal employees for emergency repairs on the water main. If you suspect this is the case, contact your local water utility company to determine the reason for the shutdown and to get an estimated timeline for the work being completed.

Clogged Toilet

A common problem that can prevent the contents of the toilet bowl from being flushed down the drain is a clog. Generally, toilet clogs are due to someone using far too much toilet paper without flushing. This can create a blockage in the drain line that prevents any additional waste from being flushed.

You can typically resolve this issue by using a plunger to force air and water through the drain line to dislodge the clog. Just make sure that the water level in the toilet bowl is low enough that plunging the toilet will not overflow the toilet. If the water level is too high, use a cup or bucket to remove the water from the toilet bowl, so that you can plunge the toilet and clear the clog.

Faulty Flapper

A weak flush could indicate that you have a faulty or damaged flapper. The flapper is responsible for sealing the opening between the toilet tank and the toilet bowl. If the flapper is warped, torn, or otherwise damaged, then it may be allowing water to flow from the tank into the toilet bowl. A toilet cannot flush properly if it doesn't have enough water in the tank.

To fix this problem, purchase a new toilet flapper that is compatible with the existing flush valve assembly. Remove the old flapper and replace it with a new flapper so that the toilet tank will fill. After this replacement, check to ensure that the toilet tank is filling properly. When it is full, flush the toilet to verify that this fix has resolved the problem.

Damaged or Obstructed Float

As indicated by the name, the float typically floats on top of the water in the toilet tank. When the water reaches a set level, the float tells the fill valve to close, preventing the toilet tank from continuing to fill. However, if the float is damaged, obstructed, or set too low, then the tank may not fill completely, leading to a weak flush. You can resolve this problem by replacing the existing float, removing the obstruction, or adjusting the float level so that the toilet fills up to the desired level without issue.

Rim Jet Blockage

Rim jets are small holes located on the underside of the toilet bowl rim. If these holes become blocked or clogged by mineral deposit build-up or any other type of debris, then it can significantly reduce the flushing power of the toilet. A toilet brush or an old toothbrush is useful for fixing this issue. Scrub the rim jets with vinegar to break up mineral deposits and remove rim jet blockages. Flush the toilet after cleaning to verify that this resolved the flushing problem.