Cistern water flowing to fill but going straight into pan

[reb78]

We have a toilet problem.... water is flowing into the cistern but is running straight into the pan, so it won't fill, wont stop when full and won't flush either.

I'm away for a few weeks so we are going to tie the float up as if it's full for now.

I've read a couple of things suggesting the flush valve has failed and can be replaced but can anyone tell me what system this is and what I need to buy? I am hoping I can do it without splitting the cistern and pan but realise that's not likely.

 

[minimutly]

@Kayos suggested one on here a few weeks ago - do a search. Mine has gone again, seems only a year or two since I changed it, blooming rubbish. Welsh water have identified these as a major issue, and are offering to fix them for free....
Nuts that something designed to save water has made the problem worse, who'd have thought it?

 

[Welderpaul]

Cistern fill valve help

Does anyone recognise this model of fill valve please as I would like to replace the seal which is leaking.

www.mig-welding.co.uk

 

[voipio]

Most modern toilet flush systems have a method of removing the water flush assembly, without having to remove the whole cistern. It may be a twist, bayonet style removal, or a couple of plastic spring clips holding it down. We had one leaking here, and it turned out to be a blistering in the surface of a large silicone rubber sealing washer. The washer was the one that moved to release the water, when the flush button was pressed. I ended up poking each of the blisters with a sewing needle, so they went flat. It's been working well for over a year, now.

 

[Blobber]

Looks like that's a twist out style?

 

[reb78]

I think it might be this?

Siamp Storm Fittings Pack 359905007

Supplied with Siamp Storm single flush outlet valve and Siamp inlet valve 99B. Sold in many Twyfords, Vitra, Lecico sanitaryware and B&Q bathroom packs.

www.sparespro.co.uk

I really hope I can get the part and quickly fix this rather than a 2 day job needing to find random size cistern to pan seals!!

 

[Welderpaul]

You undo this nut to change the siamp washer. Don't take the whole body out, it's a risk that it won't seal properly.

All you need is to change the washer.

 

[Kayos]

https://www.screwfix.com/p/fluidmaster-4550073-1-1-2-and-2-button-cable-dual-flush-bottom-inlet/58353?ref=SFAppShare

They do one with a brass tail but unless you are a ham fisted gorilla, plastic is fine

 

[reb78]

Sorry guys. I dont think its the fill that's at fault, it's the flush part. Water is coming in and pouring straight out. It has no chance to fill so won't raise the float to stop water coming in.

So it's the bit with the push 'button' on the top that's at fault I think? Can I buy just this to replace?

 

[Kayos]

Yes, if it's a twist out it's a 30 second job

 

[iNf]

You can try taking twisting it off and cleaning the seat incase some debris is keeping it open but usually it doesn't last long and you'll need to replace it. If so best to replace the whole thing, it's not difficult.
Some videos here to walk you through common problems/ replacement https://www.fluidmasteruk.com/support/
@Welderpaul it's the flush valve not fill valve faulty.

 

[gaz1]

i dont like them as there still a rubber to seal from the toilet box to the pan and once they fail its a take off and replace them

i prefer the old type flush lasted way longer than these crap things and all it is a plastic sheet that needs replacing on them

https://www.screwfix.com/p/flomasta-bottom-entry-flush-valve-pack/328JN?tc=TA6&gad_source=1&gclid=EAIaIQobChMIt8TUmqjfigMV16NQBh0rmjjzEAQYAyABEgLj6PD_BwE&gclsrc=aw.ds

older type and lasts longer without the annoying water still running into the pan

Viva Skylo Dual Flush Syphon

A traditional replacement toilet syphon. • Height adjustable: 190 - 288mm (7.5" - 9.5")• Internal overflow• Dual flush function• Multiple flushing volumes• 10 year warranty

www.toolstation.com

 

[reb78]

i dont like them as there still a rubber to seal from the toilet box to the pan and once they fail its a take off and replace them

i prefer the old type flush lasted way longer than these crap things and all it is a plastic sheet that needs replacing on them

https://www.screwfix.com/p/flomasta-bottom-entry-flush-valve-pack/328JN?tc=TA6&gad_source=1&gclid=EAIaIQobChMIt8TUmqjfigMV16NQBh0rmjjzEAQYAyABEgLj6PD_BwE&gclsrc=aw.ds

older type and lasts longer without the annoying water still running into the pan

Viva Skylo Dual Flush Syphon

A traditional replacement toilet syphon. • Height adjustable: 190 - 288mm (7.5" - 9.5")• Internal overflow• Dual flush function• Multiple flushing volumes• 10 year warranty

www.toolstation.com

If I can avoid separating the pan and cistern then I will. I always seem to have trouble.getting the right sized seals to put back together. So if anyone has pointers to the right type of replacement flush valve (if my link isn't it) I would be grateful.

 

[Bravheart]

Even at 30 seconds you and probably the floor will get wet and almost guaranteed it'll take longer. Could I suggest turning the water off and fitting an inline ball valve first. Then take your time and fit what's needed in relative comfort rather than worrying about tying up the float and perhaps knocking it off again soaking everything.

Don't ask me how I know

 

[Misterg]

If I can avoid separating the pan and cistern then I will.

The flush valve should twist & pull out without disturbing anything else.

Try this first: (Replacement washer in @Welderpaul 's post above) [<<<----EDIT: No, it's not.]

 

[Newlands]

If it is actually a Siamp flush then it might be that all you need is one of these:
https://shop.siamp.co.uk/optima-outlet-seal-5
I had to do mine recently, and trawled the local plumbers merchants, bought a load of spares that might fit and then ordered a complete new valve because I was concerned about being left without a toilet for days. As it turned out, the local Plumbase had the right part in stock, but in an unmarked packet - it looks like this:

Edit - mines a Siamp 49, and the id of the washer looks bigger than the 33 and 45 models that @Misterg shows above. And it looks like @Welderpaul is talking about an inlet valve washer rather than the outlet of the flush itself.

 

[Misterg]

And it looks like @Welderpaul is talking about an inlet valve washer rather than the outlet of the flush itself.

Oops - yes, you are right.

 

[Mick Annick]

Unlikely the seal is shot - take it out and clean it - ours regularly does it due to calcium build up.

 

[Newlands]

Unlikely the seal is shot - take it out and clean it - ours regularly does it due to calcium build up.

Yes, that might be the case. Mine had been in for about 4 years though and when I took it out it was crumbling to bits. Maybe we've got something in the water here

 

[Smallfry]

This sort of flush (push button ?) mechanism are utter sh*te. They have a flap that is pulled up to let the water out, and it drop back by gravity when cistern is empty, then the weight of water keeps it sealed on its seat.

You only need a small bit of debris or limescale to ruin the sealing. It normally gets embedded in the rubber seal, and needs to be removed and cleaned. May fix it, or my not. My experience is usually not.

Anyone reading this should check theirs. It only takes a small dribble to ramp your water bill up by a lot. Not so bad if you are paying supply only (cess or septic tank) but if you are mains drainage, it can really hurt. Had it here a couple of years ago and just this nearly doubled our water bill, and we are supply only !

Check it by looking at the water in the pan, at least an hour after last flush. If you can see it rippling or moving slightly, it is leaking. Any movement will be very small. If you then touch the back of the pan wall with some tissue, it will confirm it. It will get wet very quickly.

I will not have one of these in the house now. Both of ours have now got old fashioned cisterns with a hand lever to operate it, and a syphon inside.