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A flush toilet (also known as a flushing toilet, water closet (WC) – see also toilet names) is a toilet that disposes of human waste (principally urine and feces) by using the force of water to flush it through a drainpipe to another location for treatment, either nearby or at a communal facility, thus maintaining a separation between humans and their waste. Flush toilets can be designed for sitting (in which case they are also called "Western" toilets) or for squatting, in the case of squat toilets. Most modern sewage treatment systems are also designed to process specially designed toilet paper. The opposite of a flush toilet is a dry toilet, which uses no water for flushing.
Flush toilets are a type of plumbing fixture and usually incorporate an "S", "U", "J", or "P" shaped bend called a trap that causes water to collect in the toilet bowl to hold the waste and act as a seal against noxious sewer gases. Most flush toilets are connected to a sewerage system that conveys waste to a sewage treatment plant; where this is not available, a septic tank or composting system may be used. When a toilet is flushed, the wastewater flows into a septic tank, or is conveyed to a treatment plant.Associated devices are urinals, which dispose of male urine, and bidets, which use water to cleanse the anus, perineum, and genitals after using the toilet.

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  1. omendata

    Flush valve washer needed - nobody seems to supply this size

    Lecica Toilet is quite old (+15 years) I phoned the manufacturer but they sent me a standard washer for the Lecica Cistern flush Valve but it does not fit! Dimensions for the one i require are:- Inside diameter: 75mm. Outside diameter: 57mm.
  2. J

    Can it tell if system flush done or not?

    Hi, I had my new boiler and 13 radiators installed in July last year, but since installed all the radiators always top half hot and bottom half cold or warm. I know that if radiators top half hot bottom half cold/warm, it indicates there's sludge in there. But as the radiators were all new, so...
  3. E

    Change toilet flush side

    I'm after some advice. I am looking to move our flush from the right side to the left, so that we can cover exposed pipes on the right. There is a space for the flush on the left & can turn siphon to face the other way but the attachment for the flush to siphon is too short and to the ballcock...
  4. G

    Help, Leaking flush pipe

    I’ve discovered a slow leak behind my toilet that’s maybe been slowly leaking for a few years before we have moved in. I’ve replaced chipboard as it was soaked through. Seems to be coming from the flush pipe attached to cistern. The rubber washer seemed in ok condition, the hard plastic washer...
  5. S

    Custom Flush Pipe High Level Cistern

    Hello, I’m trying to replace an antique high level cistern with a more modern ceramic one. The flush pipe is routed in a very specific way so the new one will probably need to be bespoke. Does anyone have any experience, or at least seen, bespoke flush pipes? I was hoping they could be made...
  6. G

    Touchless Flush kits for pneumatic push button flush

    Does anyone know of any options for touchless flush kits (battery powered) for a Dudley push button, pneumatic flush? The Dudley one is well over £300 which seems really expensive when there are kits out there for non-pneumatic systems at less than £50.
  7. K

    Toilet flush problem with water coming down pan after successful flush

    Our toilet which is a year old has begun to have a problem with its flush. It flushes seemingly normally but then when the cistern has filled water comes down the pan for about 20-30 seconds then stops. Hoping somebody has a fix for this :)
  8. A

    Toilet will not flush solids

    Toilet will not flush solids
  9. Andreea67

    Solution for Geberit flush that needs to be kept pressed?

    We've recently got installed a Geberit concealed cistern and noticed only after the plumber left that the water flushes only if I keep the button pressed (for either long and short flush same situation). Is there a way to adjust this myself, or should I call back the plumber? Seems a minor...
  10. J

    New toilet not flushing as expected

    Hi, I,'m after some advice please. We have recently had a new bathroom fitted by a professional fitter. We chose the units and he purchased and installed. However the toilet that was fitted struggles to flush anything, even a few sheets of paper takes a couple of flushes. The fitter is...
  11. P

    Power Flush after visit

    Hi I have recently had a visit from an engineer as I am covered under a homecare agreement I've had for around 18 years. This was for a leaky draincock valve. When I asked them to add inhibitor due to advice I received on this forum he said he would but then pulled out a pipe clogged with...
  12. C

    Geberit flush mechanism

    Can anyone please explain how you detach the grey flush mechanism from the flush buttons? Couldnt find anything on the usual sources. Dont want to force it and break it. It's an older model Geberit flush mechanism.
  13. E

    Is a central heating system flush needed after replacing a radiator?

    I purchased a Kudox steel panel radiator to replace a radiator that developed a leak. There is a warning triangle on first page of the Installation Instructions with the following in red capital letters: ‘AFTER INSTALLATION THE ENTIRE CENTRAL HEATING SYSTEM MUST BE THOROUGHLY FLUSHED WITH A...
  14. MancAnt

    SiamP interal wall Flush not filling

    Help..... So we have an internal filled SiamP toilet push panel flush toilet system. My Son has just used the toilet and flushed it fine and then went and washed his hands. When I went to flush it after him it flushes fine but wont fill!! If you however turn on the sink or bathroom cold water...
  15. S

    Replacement Flush Button - wired

    Hi all, Somehow my daughter managed to break our flush button. I can't see a way to glue this one together- and the way that the vanity unit has been installed means I can't remove the cistern to replace everything- so can anyone suggest a replacement push button for this? Thinking that I may...
  16. T

    My double flush toilet has developed a fault. It won't stop filling eve when I pull the float arm right up. I have replaced the inlet valve diaphragm

    My double flush toilet has developed a fault. It won't stop filling eve when I pull the float arm right up. I have replaced the inlet valve diaphragm but this has made no difference What else can i try?
  17. M

    Pneumatic toilet flush is difficult to push

    I’ve installed a Geberit concealed toilet cistern. It has a pneumatic dual-flush button. The flush button is very difficult to push, once pushed it does flush but it requires a lot of effort. Is this normal for a pneumatic flush button, can anything be done to make it easier to push?
  18. C

    2.7" cistern flush

    We are trying to replace the push button flush on our toilet. We've got a replacement flush, that includes seals for 1.5" and 2" cisterns, however the diameter of the hole at the bottom of our cistern is bigger, about 2.65cm/2.7". We've attempted to use the 2"seal,with the old doughnut seal...
  19. A

    Rimless Toilet - Flush not reaching front of the bowl

    Hello All, I'm trying to install a rimless toilet and I just cannot get the flush to function as it should. Here's a video of what's going on - the water doesn't reach the front of the bowl. I've raised the issues with the supplier and after sending videos and pictures of the set up, they...
  20. X

    URGENT New flush and waste pipe issues

    I have just bought a new flush for my cistern as the old had broken however upon fitting, the new flush outlet is the same width as the pipe leading to the toilet and im struggling finding a way of connecting them. Can I just have someone tell me there is some sort of fitting or adapter I can...