toilet cistern not filling enough to flush

11 Jan 2010
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United Kingdom
Our toilet is not flushing away the content. If you take off the cistern you can see that the toilet is not filling up to the water mark. The valve is a Torbeck Float valve and the float is up to the highest setting. The Torbeck was fitted last year when we had building work done and the cistern flush was also renewed. We have had the problem ever since. Can you get different size Torbeck's? What else could it be? We have held the float down so the water fills up to the water level and then the toilet seems to flush fine.

thanks for your help
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what torbeck valve is it ?
is it bottom or side entry ?
is it one with an adjustable height on the stem, blue nut half way up the stem.
or is it a fixed height one, they come in different heights.

have you a pic ?
from your descriptions I would say bottom entry fixed height. The top of the valve is a good 2 inch below the top of the cistern. So basically we need a taller valve?
this is a fixed height one.

this is an adjustable height one with the blue nut half way down the stem.


yes sounds like you have one thats to short in height.
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The one in the top picture does allow a smaller adjustment in water level.

The float shaft has little bobbles which locks as set on to the end of the arm.

If its like that you can move the float until its just below arm.

If its like the one on the bottom picture then you can loosen the blue nutlike part ( with water supply turned off ) and raise the upper part as its a telescopic assembly.

Replacement time then.

It would be a total not recommended bodge but it might work if you put the float just ABOVE the arm.

But dont tell anyone that I said that.

Dont blame me either if it falls off and floods the toilet! But the overflow tube SHOULD contain the full flow through the float valve.

I had a similar problem and, I'm afraid, I bodged it. The bottom of the float is open and top of the float sits a good inch above the water level. I needed another half inch, so I drilled 3 holes around the bottom of the float, half an inch above the base.
My non-suggestion was based on having a hollow float!

Obviously it would not work if it had an open bottom ( top ).


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