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A cistern (Middle English cisterne, from Latin cisterna, from cista, "box", from Greek κίστη kistē, "basket") is a waterproof receptacle for holding liquids, usually water. Cisterns are often built to catch and store rainwater. Cisterns are distinguished from wells by their waterproof linings. Modern cisterns range in capacity from a few litres to thousands of cubic metres, effectively forming covered reservoirs.

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  1. J

    Can't connect cistern inlet connector because of inlet filter

    Hi. I think the title says it all really. I was just lining up pipework and stuff and noticed that the Speedfit 15mm X 1/2 BSP tap connector won't connect to the cistern inlet because the inlet filter protrudes out too far to allow the rubber washer on the connector to sit against the outer...
  2. F

    Foghorn/Splutering from cistern! Video attached

    Hi all, Had a toilet installed recently which is now making the attached sound. (No chance of him coming back to sort it...) Anyone know what's causing it? Issue coming from whatever that piece is on the right hand side (please let me know). Cheers
  3. G

    Cistern fill valve - very low pressure

    Hello, does anyone know of a side fill valve that works in very low pressure situations? I installed two separate new side fill valves on my concealed cistern today, a Fluidmaster and a Dudley, both didn't seal properly. From reading reviews and forums it looks like it's due to the very low...
  4. G

    How to put the cistern against the wall

    The toilets both have a piece of wood between the cistern and the wall.I cannot find an outlet pipe which will let me push the cistern against the wall. Do I have to get a different toilet to achieve this.
  5. M

    Mass of gunge in cold water storage cistern.

    Hi all. Hope you are enjoying the sunshine and hope no one is working in lofts at mo. Anyone seen this gunk before in a cold water storage cistern?
  6. A

    Cistern leaking water to seat area when I flush

    Hi Guys, I have a toilet where when you flush, the water from the cistern leaks out from a section of the cistern at the bottom where the seat area begins at the top just before the bowl. Was wondering how this could be happening or how it could be fixed?
  7. M

    Cistern not filling?

    Hi new to the plumbing industry, can anyone advise me on why the cistern is not filling with water but can hear the sound of water running? Would it be the side filling valve and maybe replace for a newer one? Also should the symphony i am holding have a washer at the bottom as this doesn’t...
  8. philw67

    Replace cistern mechanism

    Hi, we moved into a new house a while back and the main toilet has a large cistern and no dual flush capability. It gets used most of the time rather than the single ensuite we have so I was wondering if someone can recommend a kit to replace the lever with a two button arrangement or other...
  9. S

    Cistern problem/Meter readings

    Hi, I am just about to move into a new build property. I took the water meter readings and they read 000000,620 I had a look around the property like you do and used the toilet. When I flushed it the water kept trickling into the toilet and not into the cistern. The cistern is built...
  10. S

    Geberit enclosed cistern

    I have an older Geberit, installed in 2009 (see photo). All the videos that I can find are about much newer models. No matter where I set the fill level, it over fills and pours down the overflow into the bowl, causing the filling to continue forever. The filling mechanism is quite recent, but...
  11. 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...
  12. N

    Overfilling cistern - floating mechanism not halting inlet

    Hi everyone, First time poster, go easy on me! My toilet cistern seems to be overfilling. It's a narrow plastic cistern (not important I imagine) and thankfully the overflow pipe is doing its job. The floating mechanism is working in that it's moving up and down, though it has a lot of...
  13. I

    How to remove a glued cistern

    Morning everyone. We have a leak from one of cistern holding down bolts on our close coupled WC. This has occurred after a plumber replaced the flush valve yesterday. The problem is now that the plumber says he can't get the cistern off to replace the bolts because it is glued ( probably...
  14. A

    Cavity wall or ceiling cistern?

    I'm planning a wetroom in a very small space 1m x 2m (see attached). I want to maximise the space by having a cistern entirely in the stud wall including the waste . Two questions really 1. Is there a cavity wall cistern that fits completely inside a100mm cavity? 2. Is there such a thing as a...
  15. W

    Geberit slim cistern fill valve

    To get the latest geberit fill valve in to a slim cistern - disassemble and remove the part with "ears" that makes it too fat for the cistern width - then reassemble. Use the clip from the old fill valve to reattach.
  16. mudson

    Finding a new cistern to fit my close coupled toilet

    Hi - I have an old (maybe 45 year old) Twyfords Close Coupled toilet. The cistern has cracked, and I'd like to replace just the cistern. I'm struggling to find anything described as a close coupled cistern which doesn't have the bolt holes. I was hoping to find one with no bolt holes and just...
  17. A

    My Saneux FL2026 (concealed cistern) push buttons not working

    We have model number FL2026 concealed cistern - picture attached. The system is not working when pushing via the buttons on the plate. It used to work when we push directly after removing the plate. Even this has become hit and miss now - specially with the yellow button. The pins (used to...
  18. P

    URGENT Geberit concealed cistern Leaking into Wall…

    Hi all, I was just posting on here to see if anyone has had anything similar or can point me in right direction… I have a Geberit concealed tank within the wall so a floating toilet and over recent weeks have found that the brick work just outside of the toilet area (downstairs toilet) has...
  19. 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...
  20. P

    Roca Duo in wall cistern how to remove plate?

    Hi Guys (and Gals).... Just moved into a new house, all fine, except today the main bathroom cistern started overflowing (into the pan). I think its a Roca Duo, with the L1 plate (from the Roca website). I've watched a couple of youtube vids on how to check these etc, but I've failed at the...