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Slow Flushing Toilet - Introduction

slow-flushing-toilet-pic1What can you do about a slow flushing toilet? This problem is common in older toilets.

Not sure if this your problem? See the article 'How to Fix a Toilet' for a complete listing of all of the toilet repair topics. There are (3) Key Topics associated with a 'Slow Flushing Toilet':

Toilets that used a large supply of water would be prone to slow flushes. Hard water and sediment can also be a factor.

A toilet that flushes slowly can be very annoying. When a toilet does not flush properly, clogs are frequent. A clogged toilet is more than irritating. The dirty messy water is no fun and can be a health hazard.

In the mid nineties, toilets had to start using 1.6 gallons of water per flush. Prior to that time toilets could use 3.5 to as high as 7 gallons of water. The design of toilet would require that the full amount be used. In an effort to conserve, some homeowners would adjust the water level down. This will cause the toilet to flush slowly, since there is not enough water pressure to create the proper siphon effect.

Issues With a Slow Flushing Toilet

What Can You Save? - A plumber can usually take care of this problem in a single service call. Normally this will run from $75 to $100. One danger is that the toilet will be condemned and the plumber will try to sell you a new toilet.

How Hard Could It Be? - Fixing the common causes of a slow flushing toilet is not difficult. | These repairs will have a Difficulty Level of: Simple | These repairs require a Skill Level of: Job Jar Specialist | For and explanation of the terms in this section, see 'How to Use This Site'.

Check the Simple Things!  - Adjusting the float to set the water level to the correct height is the easiest fix. Most toilets are designed to work properly with the water level at the maximum level in the tank.

What Can Go Wrong? - Not fixing a slow flushing toilet can lead to toilet clogs. A clogged toilet can be very disruptive. Not to mention the mess that can be made by the dirty water. Another issue is that the toilet may need to be flushed multiple times, wasting water.

Fixing a Slow Flushing Toilet – The Steps Involved

The 'Next' section discusses 'Adjusting the Toilet Tank Water Level'. Check the 'Home Repair Topics Menu' at the top of the page, if this is not your problem.

Last Updated on June 18, 2013

Setting the Toilet Tank Water Level

toilet-tank-water-level-pic1Setting the toilet tank water level to the proper height will insure a toilet that flushes properly. It may make economic sense to lower the water level in the tank, to save money. However, it does not make good toilet flushing sense.

Too little water in the tank can cause the flush slowly or not at all. This will cause the toilet to clog and create and unpleasant situation. Toilets are engineered to work with a certain amount of water. Make sure that when the tank fills it is near the top of the tube for the flush valve.

See the article 'How to Fix a Toilet' if this is not your problem, it covers all of the toilet repair topics.

Toilets are designed to use a certain amount of water to flush. With the water consumption limitations imposed by the government, all of that water is needed for the toilet to work properly. Reducing the level in the tank will cause the toilet to flush poorly. A 'slow flushing toilet' is a sign of too low a water level.

What Is the Proper Toilet Tank Water Level?

toilet-tank-water-level-pic2With the lid taken off you should be able to see a round vertical tube in the center of the tank. It will have the toilet flapper and a fill tube attached to it. The vertical tube is part of the toiltet flush valve.

The proper water level for most tanks is near the top of that vertical tube. Some tanks will have a line and an indication that is is the 'fill line'. If you have markings inside your tank, you want make sure the water is set to that level.

For tanks with no markings, you will set the water level just below the top of the fill tube. Stay about 1/2" down from the top. You do not want to get too close to the top, otherwise it will run over and trickle into the tank.

Adjusting a Toilet Fill Valve

slow-flushing-toilet-pic2When you look into the toilet tank you will see off to one side another vertical elment the has a built in float on it. It will also have a tube that is connects it to the fill tube in the center. The bottom of this assembly is connected to the water supply line for the toilet.

This is the fill valve. The fill valve has a float on it that can be adjusted to set the water level in the tank. Most fill valves have a float that slides up and down on the vertical fill valve. There is a retaining clip or a screw device that allows for adjustment.

When the water is too low in the tank, you want to raise it. Simple, right? Yes it is, fortunately, the float adjusts the same way the water needs to go. To raise the water level, raise the float. To lower the water, lower the float.

A fluidmaster vertical fill valve will have an adjustment shaft with a phillips screw inset at the top. Turn the shaft clockwise to raise and counterclockwise to lower. Older ones will have a metal shaft with a spring clip on it. Pinch the spring clip and raise or lower the float as desired.

Adjusting a Toilet Ball Float

toilet-tank-water-level-pic4Some toilets will have a ball cock that acts as a float. This will be connected to a horizontal rod that is connected to the fill valve. There will be a adjustment screw where the rod connects to the fill valve.

To raise the water level you want to raise the float. Adjust the set screw or the clip on the float.The direction to turn the screw will depend on the design of the float valve. You may have to experiment a little to determine whether you are raising or lowering the float. The same rules apply with floats, raise it to raise the water level and lower it to lower the water level.

Checking the Toilet Tank Water Level

Before you pat yourself on the back for a job well done, you want to do a couple of test runs. Flush the toilet and let it fill back up.

It should stop filling at the mark on the tank or just below the top of the fill tube (approximately 1/2" below the top). If it fills too high it will start trickling into the fill tube and down into the toilet, wasting water. Make corrections as needed.

Check the water level on your tank periodically to make sure that it continues to fill properly. This will help to avoid toilet clogs and noisy water wasting situations.

The 'Next' page covers 'Removing Toilet Sediment'. The 'Previous' page is the 'Introduction' to this series of articles on a 'Slow Flushing Toilet'.

Last Updated on April 10, 2014

Removing Obstructions From a Toilet

toilet-auger-pic2The last and less desirable reason for a slow flushing toilet is an obstruction. Now this is not a slam on having children.

There are three articles that discuss 'Toilet Clogs'. See 'How To Unclog a Toilet', 'Plunging a Toilet' and 'Using a Toilet Auger'. Just about any type of obstruction can be dealt with using the information in these articles.

Children are great and well worth the few problems that they create. Sometimes, not likely the fault of the children, things get thrown in the toilet that shouldn't be there. Toothbrushes, small toys and other objects can get caught in the trap.

When objects get caught in the trap, the toilet still works, but poorly. The obstruction will catch things that go by, slowing down the operation of the toilet. The solution is to get rid of the obstruction.

A toilet auger is the best tool to use when you have this problem. The problem will likely get worse and the clogs will become more frequent. In time the plunger will no longer work and something will have to be done. A slow flushing toilet has now become a clogged toilet.

The 'Next' page is a 'Summary' of this series on 'Slow Flushing Toilets'. The 'Previous' page discusses 'Removing Sediment From a Toilet'.

Last Updated on June 18, 2013

Removing Toilet Inlet Sediment

slow-flushing-toilet-pic3Another reason for a slow flushing toilet is a clogged inlet valve. The water from the tank is fed into the bowl via an inlet that is built into the porcelain bowl.

This might not be your problem, see 'How To Fix a Toilet' or 'Plumbing Repair' for all of the plumbing related articles.

Sediment can build up in this inlet. This will cause the water coming into the bowl to slow down. As a result the toilet will not flush correctly.

Toilets are engineered to use a certain amount of water. Most people realize this. What many don't realize is that the water needs to enter the bowl in a certain amount of time.

When it gets slowed down, the engineering falls apart and the toilet fails to flush.

There are several inlets for water in your toilet. Some are under the rim. The main one is usually near the bottom where the water leaves the bowl.

Check for sediment in all of the inlets and clean it out as needed. You might want to consider wearing waterproof gloves for this activity.

You can use a small screwdriver or awl to clean out the sediment. It builds up over time and can be pretty stubborn. Try to get rid of as much of it as you can. Use a little elbow grease and get all of the sediment out of the inlet.

The 'Next' page covers 'Removing Partial Toilet Clogs'. The 'Previous' page discusses 'Adjusting the Toilet Tank Water Level'.

Last Updated on June 18, 2013

Slow Flushing Toilet - Summary

The 'Introduction' to this series on 'Slow Flushing Toilets' gave you an overview of the symptoms and problems you might be facing. It also gave you some idea what it might cost to have someone fix this problem for you.

The amount of water in the toilet tank is critical to proper flushing. The article 'Adjusting the Toilet Tank Water Level' provided instructions on adjusting it to the proper level.

Another common problem is a build up of sediment in the inlets for the bowl. If the water does not get into the tank quickly enough, it won't flush properly. See 'Cleaning Out Toilet Sediment' for a review.

'Removing Toilet Obstructions' discusses how a clog or partial clog can affect the operation of your toilet. Removing them is the only choice.

Were you able to deal with your slow flushing toilet? It may have been as simple as adjusting the float. This is especially true for older toilets. In years gone by, toilets needed a lot of water to flush properly. When the tank level gets too low, the proper siphoning will not start.

Another common problem is sediment in the inlet valve. Again, older toilets are more likely to have this trouble. Then there is the 'object' stuck in the trap. No one knows how is got there, but it sure has caused a problem. Dislodging objects is not too hard and hopefully, you are up and running again.

The 'Previous' page discusses 'Removing Toilet Obstructions'.

Last Updated on June 18, 2013

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Make sure you are working safely. See 'Home Safety Tips' and 'Electrical Safety Tips


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