Toilet not flushing

Destination

Destination

Destination

Soldato
Joined
31 May 2009
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An issue has developed within my toilet, (hurr hurr) all has been fine for years, then a stage where you had to push twice quickly to get it to flush, and now it won't flush at all, unless you take top off and push ballvalve down to overfill the cystern.

I figure the problem relates to a Split Diaphragm or broken Siphon, unable to determine which, as I drained the ******, and then went to try and remove the Siphon and find I am totally unable to do so.
I was expecting a blot externally, or some form of nut to undo, but I am unable to find any such thing. The cistern sits directly on top of the bowl, and although not fused, are tight to one another.
I can't set the ballvalve to allow the cistern to overfill either, as when the water reaches a level it start to run and drip into the bowl as some form of overflow mechanism.

Trying direct pressure to remove the siphon doesn't appear to budge it either, and i don't wish to break the thingtrying to remove it.

Any suggestions on how it is retained and how to remove/replace it?
 
The syphon says 'Derwent Macdee' Made in England.
No other markings anywhere I can find.
White and blue plastic construction.
Not my toilet, but this looks like what I see.
2445809417_361155e034.jpg
 
If you call a plumber to sort this you lose all the man points youve ever gained tbh!

I had the exact same problem last week, it'll be a split Diaphragm like you said. £5 for a new siphon from Screwfix and 20 mins to fit it and you're good to go.

You need to drain the cistern and the remove the wingnuts that attach it to the bowl and then remove the cistern from the bowl. Then simply undo the big nut on the bottom and it drops out.
 
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Right, then my issue will be isolating the toilet to actually get at it to replace the syphon. The two nuts I can under, but I can't remove the cistern easily, as I'll have to completely detact the water pipe into the tank, which has no isolator, and no valve. Means draining the roofspace tank no doubt, unless folks have a better suggestion?
 
yeah its a bitch if u dont have an isolator valve - Isnt there a kit you can get to freeze a pipe for a short period of time? Never doneit so not sure if its a good idea.
 
This happened to me, and I went the overkill route and got a whole new toilet! Luckily, I have a friend who can do such things, and fitted it for me on the cheap, so it wasn't so bad. Really appreciate his help with that!
 
Hikari Kisugi said:
Right, then my issue will be isolating the toilet to actually get at it to replace the syphon. The two nuts I can under, but I can't remove the cistern easily, as I'll have to completely detact the water pipe into the tank, which has no isolator, and no valve. Means draining the roofspace tank no doubt, unless folks have a better suggestion?
Click to expand...

Gah, yeah mine had an isolator. Still, it should still be an easy job if you can get access to your loft. A plumber will charge you a lot if the job is time consuming.

Alternatively, if the water feed to the cistern is on a flexible hose then you could possibly do the job without having to totally remove the cistern.
 
Nah its bloody metal pipe, and no give at all in the length of it, even under the floorboard it comes up from looks like it was stretched to fit at the time of construction.
 
Hikari Kisugi said:
An issue has developed within my toilet, (hurr hurr) all has been fine for years, then a stage where you had to push twice quickly to get it to flush, and now it won't flush at all, unless you take top off and push ballvalve down to overfill the cystern.

I figure the problem relates to a Split Diaphragm or broken Siphon, unable to determine which, as I drained the ******, and then went to try and remove the Siphon and find I am totally unable to do so.
I was expecting a blot externally, or some form of nut to undo, but I am unable to find any such thing. The cistern sits directly on top of the bowl, and although not fused, are tight to one another.
I can't set the ballvalve to allow the cistern to overfill either, as when the water reaches a level it start to run and drip into the bowl as some form of overflow mechanism.

Trying direct pressure to remove the siphon doesn't appear to budge it either, and i don't wish to break the thingtrying to remove it.

Any suggestions on how it is retained and how to remove/replace it?
Click to expand...

Typically the diaphram in the unit splits, so the suction required to initiate a flush isn't there.

With common units you can replace the diaphram, but typically you'll need to replace the whole flush mechanism.

If it's a straight forward one you can get one from any DIY place and fit it in under an hour easily...


Only issue - which I believe you're having - is ensuring no water is coming into the unit. If you don't have a tap to turn it off, you'll have to cover/bung the outlet from the tank in the loft?
 
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From a plumber,

get a new toilet siphon (make sure its the correct height) be prepared to buy new wing nuts, back plate and donut washer (the thing the cistern sits on) as these can ware out and cause problems.

as for water isolation, as above drain the whole tank in the loft after turning the mains off, also keep a tap open at lowest point in case water creeps through! Ooo and slap an isolation valve on the pipe work if you feel up for it, only 2 compression joints (just need a spanner) and a bit of measuring :)
 
Basically as above but I'd be surprised if there isn't an isolator on the outlet of your cold water tank (the one in the roof space)? If there is its a easy turn it off and turn on a tap lower in the system to drain whats in the pipe. If not then as varial says drain the lot, I would defo fit an isolator while you have it off though.
 
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varial said:
as for water isolation, as above drain the whole tank in the loft after turning the mains off, also keep a tap open at lowest point in case water creeps through! Ooo and slap an isolation valve on the pipe work if you feel up for it, only 2 compression joints (just need a spanner) and a bit of measuring :)
Click to expand...

+1
This is exactly what I had to do. Not a big deal, just can take a while to drain a large tank...
 
laiman said:
Basically as above but I'd be surprised if there isn't an isolator on the outlet of your cold water tank (the one in the roof space)? If there is its a easy turn it off and turn on a tap lower in the system to drain whats in the pipe. If not then as varial says drain the lot, I would defo fit an isolator while you have it off though.
Click to expand...

Quite often there's a tap somewhere to stop the downstairs feed, eg: upstairs in an airing cupboard or somewhere!?
 
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