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Toilet Overflow Pipe!

Postby rappo » Thu Jul 03, 2008 8:32 am

Hi all,

I am in the process of putting in a new en-suite at my house and the question I have is:

I am going to replace the toilet, but have noticed that there is a white plastic overflow pipe coming from the back of the cistern which goes through the wall outside. Whilst this is not a problem, I have been told that new style toilets do not need a waste pipe and I could effectively remove said pipe from the wall. Is this correct?

Thanks :roll:
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Simply Build It

Postby EyeTry » Thu Jul 03, 2008 10:49 am

Check the run of the overflow pipe inside and outside to ensure it is one and the same. (I have two suites / overflows - one has a t-piece to break the air flow coming into that cistern, the end of the other is screened by soil stack) If you have the Drop-Valve type of flush in the cistern then Yes, it does function as the overflow. Look straight down the centre and you`ll be looking into the rear of the pan - where the flush starts.

The Drop-Valve "plugs and twists" into the base assembly (rather like a bayonet fitting lamp-bulb) and the flush is GREAT, better than the syphon style!! Obviously you need to check the height of the rise and fall "tube" against the usual water level and trim any excess height - otherwise the water level could just rise and rise and come over the top of the actual cistern before it reached the top of the valve..... .

You can buy a "Blanking Off Piece" (59 p at Screwfix) that fits the original overflow take-off hole like a blanked-off joint.

Pull the old pipe through and make good the holes inside and outside. (I`m doing one where I`ll partly stuff a plug of loft insulation in the tube - so as I pull the tube outside the plug will lodge and block the exit hole under/behind the corner bath. Otherwise I couldn`t reach that hole. Good luck EyeTry
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Postby htg engineer » Thu Jul 03, 2008 1:28 pm

Yes, most new toilet cisterns have a syphon with a integral overflow.

If the cistern overfills, the excess water will be discharged via the syphon down the toilet pan, whereas older cisterns it would run down the overflow pipe to outside.

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