My Toilet Wont Flush – How to Fix my Toilet Flush

My Toilet Wont Flush!

A very frequent problem in homes is the loo not flushing properly. If the toilet worked properly and then stopped flushing despite how vigorously the handle is pulled, there are only two probable answers:

• Your handle is not connected to the flushing mechanism in the cistern
• The flush diaphragm is split

A cistern allows water in through a valve located just inside the cistern. There are two main types of valve. One, the most common, is the ball valve. You can get a ball valve repair kit here. The second, ever more widely used is the quieter Torbeck valve. Both operate on the same principle. The water inlet is controlled by a valve which is opened and closed by a lever. The lever or “Float arm” is raised and lowered by the water in the cistern (this is exactly the same system as that used in cold water tanks in most lofts).

Once the water is in the cistern, a flushing mechanism lets it out again. The most popular flushing mechanism is the toilet siphon. The handle is attached, via a wire, to the top of the flush siphon. When the lever is depressed, or the chain pulled, the flush diaphragm is pulled upwards on the diaphragm frame.

Because of the frame underneath the flush diaphragm the water cannot escape and is drawn up and over into the flush pipe where it runs straight into the toilet bowl.

If the flush diaphragm is split however, the pressure of the water as the diaphragm is drawn up the chamber, simply pushes through the split and does not allow any resistance. The more you flush, the bigger the split gets. Time to change the diaphragm!

A split diaphragm can be replaced by turning off the water to the cistern, flushing the toilet and soaking up any remaining water with a sponge. Once the cistern is empty, unclip the connection between the handle arm and the flush unit.

Release the back nut under the cistern and pull the flush unit clear. Unclip the bottom half of the connection clip and pull out the frame which holds the diaphragm. (There may be a spring over the central dowel, don’t forget to return this when re-assembling) Unclip and slide off the diaphragm, replace and re-assemble.

Take a look at our video sections on toilets and also our section on plumbing tips to watch a couple of films that deal with a toilet not flushing and an overflowing toilet.