Leaky toilet cistern - Advice on flexi hose

[Bidge]

Hi my toilet is leaking both from the water inlet and from the existing copper piping. I'm usually quite handy and many many years ago, I replaced the water inlet for this cistern.

However last week, it began leaking, initially from the copper piping leading into the cistern. I tried to tighten things up slightly and arrest the leak, but disturbing the piping only made matters worse and instead of one leak I had multiple leaks coming from the set-up. I live a house that is in shielding due to COVID, so I can't get a plumber in to fix the issue. Therefore, I need to fix it myself. I even resorted plumbers mate to try and stop the water coming out, which has partially solved the problem, but to use the toilet I am living off the isolation valve and having to turn it on and off every time after someone uses the toilet.

So I have been looking parts and need advice on whether I can use them to replace the faulty/leaky areas.

First up I was going get a Fluidmaster 1/2" Brass Shank Valve Bottom Entry to replace my current one, as its almost a direct replacement apart from mine is plastic, rather than brass shank.

My problem is that my copper piping that leads into this is not straight and was bent to shape by the plumber who converted our bathroom into a wetroom for my disabled wife.

So I was I thinking that I could maybe get away with using a flexi hose to replace the copper as I have no way of bending new copper to shape. But I don't know if that is something that can be done or not and thus this is where I need advice.

My isolation valve looks to be the same as this a 15mm x 15mm valve. It has plastic piping leading into it on one side and the bent to shape copper piping leading out on the other.

So is there a flexi pipe that is suitable to join the current isolation valve to the Fluidmaster bottom entry valve?

Any help would be greatly appreciated, because if I can't fix this, we will need to live like this for several more weeks until shielding is eased and we can get a professional in.

 

[JCplumb]

If you're using a flexi, this is the one for you:
JG Speedfit 15mm 1/2 BSP 300mm Flexi Hose 15mm x 1/2" - https://www.toolstation.com/jg-speedfit-15mm-12-bsp-300mm-flexi-hose/p63534
You'll need to install the fill valve (good choice of valve btw) then offer up the flexi so you can see where you need to cut the copper pipe. No tight bends, twists or kinks in the flexi.
Be sure to use a 15mm copper pipe cutter for the copper pipe as it will round the edge nicely so that it will go into the push fit end of the flexi without causing damage.

 

[Bidge]

If you're using a flexi, this is the one for you:
JG Speedfit 15mm 1/2 BSP 300mm Flexi Hose 15mm x 1/2" - https://www.toolstation.com/jg-speedfit-15mm-12-bsp-300mm-flexi-hose/p63534
You'll need to install the fill valve (good choice of valve btw) then offer up the flexi so you can see where you need to cut the copper pipe. No tight bends, twists or kinks in the flexi.
Be sure to use a 15mm copper pipe cutter for the copper pipe as it will round the edge nicely so that it will go into the push fit end of the flexi without causing damage.

Thank you for the advice, it's very much appreciated. I already own a pipe cutter, so no problems on that front. There shouldn't be any tight bends (I hope) in the flexi, as the current copper piping only bends back about the width of two copper pipes, as it rises from the isolation valve to the inlet.

Is there any way though that I can use just a Flexi without any copper piping and if so, are you able to advise which one? My ideal would have been a Flexi that screwed directly onto the isolation valve and the inlet. Its a very short run (under 30cm), between the current isolation valve and the cistern where I'll be installing the the new fill valve. If it's not possible though, it's not possible and I'll follow what you have advised already.

Cool, good to hear that the inlet is good choice. Thank you. I guessed that the brass thread would be superior to a plastic one.

 

[JCplumb]

The problem with most flexi tap connectors is that they are either compression or push fit on the end that doesn't join to the flush valve spigot. So they are made to attach to 15mm tube.
For some reason, the flexis that come with monobloc taps usually have a tap connector instead of a compression or push fit connector, so they're designed to fit onto a 1/2'' male union.
You can get them where it's a 1/2'' tap connector on each end that would be the type of flexi you're asking for. I've seen them online but never noticed them in merchants.
Many people including plumbers join a tap connector end onto a compression fitting like your ISO valve, so (against official advice) you could use one of these but they're not made to do this as the sharp edge of the compression fitting is designed to compress an olive and not sit against the rubber seal of a tap connector and can cut into the rubber of the tap connector which may end up failing.
So officially I couldn't advise you to do it that way, having said that it is really common and I can't remember ever finding one that leaked because the rubber had been cut through.
Officially you should use a tap connector like the one I linked to in my first post and join it to 15mm tube.

 

[Bidge]

The problem with most flexi tap connectors is that they are either compression or push fit on the end that doesn't join to the flush valve spigot. So they are made to attach to 15mm tube.
For some reason, the flexis that come with monobloc taps usually have a tap connector instead of a compression or push fit connector, so they're designed to fit onto a 1/2'' male union.
You can get them where it's a 1/2'' tap connector on each end that would be the type of flexi you're asking for. I've seen them online but never noticed them in merchants.
Many people including plumbers join a tap connector end onto a compression fitting like your ISO valve, so (against official advice) you could use one of these but they're not made to do this as the sharp edge of the compression fitting is designed to compress an olive and not sit against the rubber seal of a tap connector and can cut into the rubber of the tap connector which may end up failing.
So officially I couldn't advise you to do it that way, having said that it is really common and I can't remember ever finding one that leaked because the rubber had been cut through.
Officially you should use a tap connector like the one I linked to in my first post and join it to 15mm tube.

Thank you again. Now I have much to think about.

Completely understand the issue you are describing. Not sure what way I want to go now. I had been thinking along the idea that if I could use a Flexi that screwed onto both sides (the ISO and the inlet) it would have been the least hassle method to sort it it and get us through shielding with a working toilet again, but I 100% hear your warnings loud and clear and it may be better just to do it the correct way that you initially described, as it will only be a little more effort.

Thank you again and please stay safe.

 

[Roy_66]

Thank you for the advice, it's very much appreciated. I already own a pipe cutter, so no problems on that front. There shouldn't be any tight bends (I hope) in the flexi, as the current copper piping only bends back about the width of two copper pipes, as it rises from the isolation valve to the inlet.

Is there any way though that I can use just a Flexi without any copper piping and if so, are you able to advise which one? My ideal would have been a Flexi that screwed directly onto the isolation valve and the inlet. Its a very short run (under 30cm), between the current isolation valve and the cistern where I'll be installing the the new fill valve. If it's not possible though, it's not possible and I'll follow what you have advised already.

Cool, good to hear that the inlet is good choice. Thank you. I guessed that the brass thread would be superior to a plastic one.

For a temporary solution, you can get an all in one for tap to push fit with built in iso valve e.g.

https://www.NoLinkingToThis/p/hep2o...uX6elKh5OxpvVkGcrHAnS5sY-dZutFHRoCiSAQAvD_BwE

Would that help your space problem?

Silly question first though. I think you said the pipe out the floor was plastic but not given us the spec (what colour is it if no markings). I've guessed Hepworth above, where brand name is hep2o I.e. a pun on H2O i.e. water. That's an "O" on the end then not a zero if you are googling. Other common one is John Guest or JG. For JG you don't need a removal tool to get the fitting off, just push back the collar towards the fitting and pull out the pipe. I'd only do the above as a temp solution. Note there should be a removable insert inside the plastic pipe when you get the fitting off e.g.

https://www.NoLinkingToThis/p/hep2o...KSecXaW0hb3Vc04Z6YlvlwYrZfv6Y2jRoCl88QAvD_BwE

Professionals please correct any blunders I've made here.

If you can easily take a photo, that would help with answers.

And the very best of luck. Fill some buckets with water first, and some empty pop bottles to make the tea (but you know all that)

Cheers,

Roy (a very amateur plumber)