Bathroom Cistern slow fill - Help!

rhysduck

rhysduck

rhysduck

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Caerphilly
Afternoon,
The cistern in the bathroom (toilet) is very slow filling... like very very slow. Takes about 15 minutes to fill.

I took it all apart and couldn't see anything obvious... I replaced the diaphragm with one of these (https://www.diy.com/departments/plumbsure-rubber-float-valve-diaphragm-washer/178444_BQ.prd) which is identical to the current one but on doing that the cistern wouldn't stop filling up! Even when pulling the float/rocker assembly thing up a little it would just carry on filling!

Is there anything else I can try please before getting a man in?

The seal/diaphragm sits at the top of the plastic bit on the left side of the picture.
IMG-20200202-202132.jpg


Thanks
 
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I tend to just replace the entire filling assembly as they get scaled up so badly there is little point in trying to repair them.

It’s a fairly easy job, turn off the water at the service valve, empty the water, undo the bolts that hold it in. Swap it for a new one and put it all back together.

I would suggest refreshing the flusher mechanism at the same time if it’s also fairly old. Your already half way there and they don’t last for ever. Admittedly this does make it a bigger job but it’s well worth it spending the time doing it now rather than having to do the job again in the near future.

The parts for both are generally very cheap from screwfix or similar.

Watch a few videos online, it’s pretty easy, I’d say it will take you about 2-3 hours if it’s your first one. The most difficult/time consuming part is getting the old bolts off what couple the cistern to the toilet if they have rusted up (replace these too). But that part isn’t required to just replace the filling valve of you prefer not to do the whole lot.
 
Both syphons and fill valves are so cheap I wouldn't bother trying to repair them. I replaced both for my mother a couple of weeks back and it was under £20 for the pair.
 
b00merang69 said:
Assuming its not restricted by inlet valve (you would know if you had done this if it was working before).

Replace the whole thing with this : https://www.amazon.co.uk/gp/product/B004O8601M/ref=ppx_yo_dt_b_asin_title_o09_s00?ie=UTF8&psc=1


311cun-YOu-AL.jpg
Click to expand...

we have the same (design) the water comes out the base so low noise too.

OP also check that the valve doesn’t have any grit in it - I found a stone in ours that stopped the valve from shutting of.. I suspect the kitchen replumbing somehow got a stone in the pipe..
 
Thanks guys.

Would that Fluidmaster be a direct replacement do you know or would I need additonal hardware to connect to the inlet pipe? I'm pretty sure the inlet pipe on mine goes direct to the cistern (i.e. no fitting outside of the cisterm that the brass pipe would connect to) so I'm thinking that the brass thread part would sit proud (underneath) the cistern? Can someone confirm? I don't want to be spending extra to not having it fit.

I can't see any grit at all in the valve (assuming this is part of what I tried to replace) and flushed it with clean water a few times to ensure so. That was my first thought but doesn't appear to be.

RE: Inlet valve. Haven't touched this at all so it can't be that unless it's seized but it hasn't been touched .
 
Take photo of bottom of cistern where it comes out but from your internal photo it looks the same with a white plastic threaded part underneath (my old one was plastic but can leak over time so brass is better).
 
All the valves I've seen have had standard fittings.

If you remove the existing fill valve you'll be able to compare it to what you've bought before you remove it from its packaging.

If you want to be sure, remove it and take it to a plumber's merchant and ask them for a direct replacement.
 
were you saying it was still slow to fill still (but would also not stop), when you had changed fill diaphragm ?

... was the slow to fill partly because water is not stopping flowing into the bowl after it is flushed, if so the syphon valve may be the issue, those, are more problematic, suffering from slime/debris, in my experience.

new mechanisms are often poorly made, at the £15 price point, so I'd be considering a soak/scrub in diluted vinegar .. had used cheap stuff from JS
looks like the fill valve could be disconnected at the lower blue ring nut.
 
jpaul said:
were you saying it was still slow to fill still (but would also not stop), when you had changed fill diaphragm ?

... was the slow to fill partly because water is not stopping flowing into the bowl after it is flushed, if so the syphon valve may be the issue, those, are more problematic, suffering from slime/debris, in my experience.

new mechanisms are often poorly made, at the £15 price point, so I'd be considering a soak/scrub in diluted vinegar .. had used cheap stuff from JS
looks like the fill valve could be disconnected at the lower blue ring nut.
Click to expand...

Yes, still slow to fill after changing out the diaphragm but would not stop filling (even lifting the rocket assembly connected to the float).

Water is flowing into the bowl through the siphon valve just fine. Plenty of flow just like normal.

b00merang69 said:
Take photo of bottom of cistern where it comes out but from your internal photo it looks the same with a white plastic threaded part underneath (my old one was plastic but can leak over time so brass is better).
Click to expand...

Will do when I'm home later.
 
b00merang69 said:
Take photo of bottom of cistern where it comes out but from your internal photo it looks the same with a white plastic threaded part underneath (my old one was plastic but can leak over time so brass is better).
Click to expand...

Here ya go :) Please excuse the general filthyness!
IMG-20200210-165736-1.jpg
 
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