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

[toyfish]

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?

 

[ShaunCorbs]

New fill valve

 

[Deleted member 120897]

What type of inlet valve is it?

 

[toyfish]

How od 8bk ow which type. A fellow resident directed me to a standard replacement inlet valve diaphragm
This has not helped.

 

[toyfish]

Pic of valve

 

[ShaunCorbs]

Ideal standard

 

[Deleted member 120897]

So either adjustment is not correct or as Shaun said new valve. There could be debris, or something holding it off, but other than that it’s a valve issue.

 

[toyfish]

So either adjustment is not correct or as Shaun said new valve. There could be debris, or something holding it off, but other than that it’s a valve issue.

Thanks. What adjustment is available? Lifting the float arm right up doesn't shut off the flow so no point adjusting the float

 

[Deleted member 120897]

Thanks. What adjustment is available? Lifting the float arm right up doesn't shut off the flow so no point adjusting the float

The only adjustment is the float arm, I’ve had some that don’t shut off when fully up, try a gradual lift (as this is how it would shut off) and see if that works.

 

[Ric2013]

Could be the equilibrium chamber isn't sealing when the arm is lifting and so it won't shut off. Debris on the rubber bit that seals the equilibrium chamber that forces the diaphagm to shut? If you don't have a clue what I'm on about, better to replace the valve really, and, realistically, modern fill valves are highly strung affairs that you sometimes can't see anything wrong with - and yet...

Also sometimes those Armitage Shanks valves don't seal with low water pressure, so if you've shut down any stopcocks or isolators recently, try opening them again.

 

[Ric2013]

The only adjustment is the float arm, I’ve had some that don’t shut off when fully up, try a gradual lift (as this is how it would shut off) and see if that works.

Yes! I've had an AS fill valve that wouldn't re-seal if it opened up with an already full cistern - it only shut off with a gradual lift from an empty cistern.

To be annoying. (I suppose it also helps alert the homeowner to a dripping flush valve).

 

[toyfish]

Thanks guys. I've already replaced the rubber thingy to no avail. Do I just need to replace the whole unit? Are they easy to get the right model?

 

[ShaunCorbs]

Fluidmaster pro fill valve with brass shank

 

[Ric2013]

Thanks guys. I've already replaced the rubber thingy to no avail. Do I just need to replace the whole unit? Are they easy to get the right model?

No, the other rubber bit no one ever talks about. Which is not a common failure, but in theory it could.

You can replace the whole unit if you like. Most fill valves are universal - you just need a bottom inlet model that will physically fit that cistern. We all have our favourite brands if you care to search what we've previously discussed on the forum, but let's start that one up again as it's boring, basically.

EDIT - Shaun, you beat me to it. But I'm not taking part.

 

[toyfish]

Fluidmaster pro fill valve with brass shank

This fella? Fluidmaster 1/2" Brass Shank Valve Bottom Entry - https://www.toolstation.com/fluidmaster-12-brass-shank-valve/p32359

 

[ShaunCorbs]

Yep less chance of cross threading when it comes to the bottom nut

 

[Chriswareham]

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?

Replace the valve as the diaphragm has not been fitted properly.
There must be water coming from the pin so that it builds up pressure on the - side of the valve so that it shuts off