Toilet Won’t Flush? How to Fix it in Minutes

Last Updated on May 18, 2022 by toilethaven

Why is It Difficult to Flush My Toilet?

There are several reasons why your toilet is not flushing completely/all the way. Most of these are problems which you can easily fix by yourself. A toilet that won’t flush is a great inconvenience and that is why you should fix it ASAP.

If your toilet won’t flush, most likely it is partially clogged, the water level in the tank is too low, the flapper is not opening fully or the handle is disconnected/broken. Another reason could be that the the rim holes and/or siphon jet are clogged, restricting the flow of water.

To fix a toilet that won’t flush, adjust the water level in the tank, clean the rim holes and siphon jet, fix/replace the flapper and make sure that the flushing handle is not clogged. If the toilet won’ flush but water rises, unclog the toilet drain line or plumbing vent.

In order for a toilet to flush properly, a large amount of water needs to be dumped in the bowl within a very short period of time. It is the action of dumping a lot of water in the bowl quickly that triggers the siphon effect at the toilet trap. If this process is compromised, your toilet won’t flush as you would want it.

To fix a toilet that won’t flush:

  • Unclog the toilet
  • Open the toilet shut off valve
  • Adjust the toilet tank water level
  • Replace a warped/worn out flapper
  • Fix a loose toilet handle
  • Unclog the rim holes/siphon jet
  • Adjust the length of the flapper chain

If you have a dual flush/push button toilet that won’t flush, makes sure that the buttons are springing back up after flushing, or that the seal/wash is not worn out or warped. Cleaning the seal and push buttons will most of the fix the problem.

How Do You Fix a Toilet that Won’t Flush?

Here are the reasons why your toilet won’t flush in more details:

1. It is clogged

You toilet does not need to be fully clogged for it not to flush. Sometimes the toilet is partially clogged. What this means is that it will drain the water and urine but the toilet won’t flush solids.

If a toilet is partially clogged by a bar of soap or a baby doll for instance, you will notice that it won’t flush away the solids. The water will rise in the bowl then drain slowly. Mostly this clogs are trapped in the toilet trap and unclogging the toilet is therefore not hard.

The toilet could also be fully clogged which means even the water is not draining. When you attempt to flush such a toilet, it won’t flush but the water rises in the bowl and does not drain.

To avoid this problem in the future, avoid flushing items that are not supposed to be flushed. These include sanitary pads, non-biodegradable wipes, broken glasses, baby diapers etc. Don’t use too much toilet paper also.

Here are 3 ways to fix a clogged toilet that won’t flush due to clogged drain line:

Plunge It

A toilet plunger is a simple but effective tool used to unclog a toilet. It has a rubber cup at the front that makes a seal with the toilet outlet.

To plunge effectively, put the plunger on the toilet outlet leaving only a small opening. Plunge downwards slowly to remove the air through the small opening then seal all around the toilet opening. This creates a vacuum inside the plunger.

Also, make sure you are using a flange plunger and not a flat-bottomed plunger. It will seal properly around the toilet’s drain for maximum pressure application on the clog.

Plunge aggressively and hopefully the clog will be dislodged. In most cases the plunger is enough to unclog a toilet and your toilet will resume flushing well. More details on effective plunging in this post.

Snake It

A toilet auger is a coiled cable with a head that has blades and a cranking handle. Unlike a plunger, it goes inside the toilet drain to act on the clog directly.

Carefully guide it through the toilet outlet being careful not to scratch the toilet bowl. Once you get to where the clog is, start cranking the handle slowly and increase intensity with time. If it feels hard remove it out immediately.

A toilet auger will either shred the clogs into small pieces which will flow down the drain or it will hook and pull them out.

There are also a couple of ways to flush a toilet if you don’t have a plunger or snake. Read more in this post.

Call a Plumber

Unlike the normal toilet auger which is about 3 to 6 feet, a professional plumber will have a motorized auger which can reach a clog more than 100 feet away. They also have more experience so don’t hesitate to give them a call.

2. Water Level in the Toilet Tank is too Low

Sometimes your toilet won’t flush and it is not clogged. In this scenario, the water level in your toilet tank is probably low than required. When the toilet tank does not have enough water, the little water will not have the force required to flush the toilet.

The water level in the toilet tank is controlled by the fill valve and the toilet float. The fill valve is connected to the water supply line and also to the toilet float. The toilet float moves down when the toilet is flushed, and opens the fill valve.

As the water starts filling the tank, it moves up gradually until its set height. If the toilet float height is set too low, the water level will also be too low and the toilet won’t flush properly.

Note: Toilet tank not filling? Here is how to fix it.

How to Adjust Water Level in a Toilet Tank

Old toilet models use a float ball but modern toilets use a float cup which is mounted alongside the vertical body of the fill valve. To adjust a toilet float you will only need a screwdriver.

  • Turn off the toilet shut off valve. The valve is behind the toilet. Turn it clockwise.
  • Flush the toilet and hold the lever down to remove most of the water.
  • If you have a float ball type, look for a screw on top of the fill valve where the float arm is connected to the fill valve.
  • Turn this screw clockwise. Keep checking by opening the shut off valve and confirming the water level is where it should be. The water level in the toilet tank should be ½ inch below the overflow tube.
  • If you have a float cup, look for a big plastic screw alongside the float connected to the fill valve and the float cup. Turn it clockwise.
  • Keep checking the water level by opening the shut off valve and flushing the toilet until the water level in the tank is just about ½ inch below the overflow tube.

For a detailed guide on how to adjust the water level in a toilet check out this post.

3. The Flapper is Warped/Worn out

toilet-won't-flush

A toilet flapper is a rubber seal at the bottom of the toilet tank. It is sits on the toilet flush valve and is connected to the toilet handle using a lift chain.

During flushing, you pull the toilet handle down, the lift chain lifts the flapper off then water rushes out of the flush valve to the toilet bowl. After flushing, the flapper falls back and makes a watertight seal allowing the tank to fill with water for the next flushing cycle.

If the toilet flapper is worn out it will not seal properly. It could also be that mineral deposits or dirt is trapped underneath the flapper and therefore it cannot seal properly. This will result into a continuously running toilet which means your tank won’t have enough water during flushing.

How to Replace a Toilet Flapper

If your toilet flapper is worn out or simply warped, you will need to replace it. Flappers are cheap and easy to replace. If on the other hand the flapper is in good condition just that it is dirty, you will need to clean it then install it.

To remove the flapper, unhook the lift chain and slide it out. If it is dirty clean it with running water in a sink. On the other hand if it is old and worn out just slide in a new one.

Before removing the toilet flapper ensure you have turned off the water supply to the toilet and flushed the toilet.

4. Lift Chain is Unhooked or Slack

The lift chain is responsible for lifting off the toilet flapper from the flush valve during flushing. When the toilet is not in use, it is normally slack and only gets tension once the toilet handle is pushed down.

If the lift chain is too slack, it means the flush valve will not open fully and hence less water will enter the bowl. In this case your toilet won’t flush all the way. Ideally the lift chain should have a ½ inch slack.

Another problem associated with a toilet lift chain is where it hooks up to another part of the toilet tank. You can feel this from the handle where it feels hard and can’t move all the way down.

How to Fix Toilet Lift Chain

  • Lift the toilet tank lid and place it in a safe place.
  • Check to see if the lift chain is disconnected or hooked to anything else apart from the flapper.
  • If it is not, hold the chain and lift the flapper off.
  • If the toilet flushes well, then lift chain is slack and will need to be adjusted.
  • If the toilet chain is unhooked from the flapper hook it up and place the toilet tank lid back on.

5. Flush Valve is Cracked

An overflow tube is a large tube in the middle of the toilet tank that directs excess water in the toilet tank down to the toilet bowl to avoid overflowing. Ideally, the water level in the toilet tank should be slightly below the overflow tube.

If the overflow is therefore cracked vertically, water in the tank will continuously run in the toilet bowl. The end result is that the toilet won’t flush all the way because it will not have enough water to forcefully clear the waste from the bowl.

In this case you will need to replace the flush valve which is inexpensive. Check out how in this post.

6. Toilet Bowl Rims Holes/Siphon Jets are Clogged

siphon jet

The rim of the toilet bowl has holes evenly spaced, through which flush waters enters the bowl. With time, the holes can become clogged by mineral deposits present in the water especially calcium. Hold a small mirror under the toilet rim of the bowl and check the status of the rim holes.

Some toilets have a siphon jet at the bottom of the bowl facing the toilet trap directly. It can also be badly clogged by mineral deposits causing a slow/weak flushing toilet.

If they look clogged, remove the toilet tank lid and pour a small amount of vinegar through the overflow tube. Since it is not possible to have the vinegar in the rim for long, pour the vinegar in little amount frequently taking intervals of 10 minutes for about one hour.

After about an hour, take the toilet brush and aggressively clean the rim of the bowl. Pour a little vinegar and brush some more.

In addition to vinegar, you can use a thin wire or Allen wrench to unclog the holes one at a time. Insert the wire in each hole and rotate. Flush the toilet as you clean to wash down the scum.

For more information check on this check out this post.

7. Toilet Shut off Valve is Closed.

The toilet shut off valve is the knob-like valve on the wall behind the toilet. A water supply line runs from the shut off valve to the toilet tank where it supplies water to the fill valve.

If a toilet won’t flush and the toilet is empty, there is a possibility that the shutoff valve is turned off. To fill the tank with water simply turn the valve counterclockwise all the way. Some shut off valves are a little different whereby you will need to push the valve handle inside.