Plumbing advice

Soldato
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Ok, so I've noticed a dripping leak on the downstairs toilet pipe into the cistern. It's dripping from the joint to the left of the isolation valve. I've shut it down and emptied the cistern for now to stop it. Is it an easy job to replace this piece of pipe?



Bear in mind I'm not a plumber but I'm fairly handy DIY wise :)
 
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Bat

Bat

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Might be as simple as nipping up that brass compression nut a bit with an adjustable spanner. If it's the fill valve itself, then yes, quite straightforward. The copper pipe itself is most likely fine and can be reused.
 

Pho

Pho

Soldato
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Failing that there's probably a washer inside the connector which might have worn down causing a leak.

You could try wrapping some PTFE tape around the washer and also around the threads the nut goes onto (wrap in the same direction as the nut tightens) to see if that helps.

Gas PTFE tape which comes on a yellow roll is a bit thicker and easier to work with than the white one and you'll need to wrap it around less.
 
Soldato
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Looking at that photo there is no reason why you would need ptfe tape...there are no threads that need it. Just loosen the nut and put some jointing compound on the olive.
 
Soldato
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If it's dripping from the brass nut then it's probably the fibre washer that has perished. You'll need a new one when you remove it as they seem to make them from carboard which dissolves super easy these days.

I think they are called ' TAP CONNECTOR WASHERS 1/2" ' or ' Fibre Washer for 1/2" BSP Tap Connectors '
 
Soldato
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All 3 joins in the pic are joined differently so it's important we establish which one we're talking about. Is it the join between the 45 degree copper pipe and the straight section of copper pipe (both painted white)?

I think that is what you're saying, which would be a bit odd as it looks soldered to my untrained eye and, of the 3, the least likely to fail.

Are you sure it's not running down from the nut at the top? Bog roll is a handy tool to establish exactly where a leak is happening :)
 
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Soldato
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It seems to be leaking from the join between the bend and the straight pipe.

That's an odd place to leak, I'd expect it would be more likely to leak from the brass nut but it may be difficult to see and will pool / drip from the lower joint.
if you tie a thin bit of kitchen roll around just under the brass nut you'll see it comes from there.

It could also be condensation, if it's only a small amount then water is very cold this year so you may get some condensation on the pipe after flushing.

If you want an easy fix you can use a flexi hose though it won't look as neat.
 
Soldato
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Don’t use PTFE tape that stuff rubbish, use thread sealant tape like Loctite 55 far superior and it’ll seal fine.
PTFE tape is not meant to seal things, it's used to lubricate the threads / make it easier to tighten threads.

Most people think it's designed/meant to seal because it's a bit of a hack, because it's the thing most people working on plumbing have and slapping on more PTFE can be a quick fix but using it to seal is a bit of a bodge.
 
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Soldato
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21 Jan 2010
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Bit of a pain the shortest you can get is 300mm though

Hmm, done a bit of measuring and it looks more like both connections are 3/4
I don't think you can put a tap connector directly onto a compression valve. They are made for compression fittings. If you want to do as suggested you'll need a bit of copper and then come off of that.

How far away is the stop ****?

I'd be tempted to clear some paint, cut the whole thing back to the right hand side of the isolation valve, and fix a pushfit to 3/4" tap connector.
 
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