Basin bottle trap leaking at join to waste

27 Jan 2004
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United Kingdom
Thanks for the top advice on stopping the leak from within the basin and around the waste.

Now we've a new problem! Where the square chrome bottle trap meets and connects to the bottom of the slotted waste, the two pipes butt together with a flat rubber washer between them. A nut then screws from the bottle trap onto the thread of the slotted waste. However, a few seconds after you run the tap or empty the basin, water starts to drip out of the underside of the nut.

We thought at first it was the join between the nut and the thread but PTFE tape has not solved it.

Has anybody got advice on what you can do when the narrow threaded section from the waste just butts up to the pipe into the bottle trap?

The waste is a Bristan push button waste and the bottle trap is the Picasso as sold by Crosswater (but from their manufacturer in Italy). The underside of the sink is visible as it's a wall hung basin so whatever we do needs to look nice!

I've added a photograph of the trap and the technical drawing that came with it to my photo album.

View media item 18799 View media item 18800
Any advice welcomed :)
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If the waste and the trap aren't meeting square then the flat rubber washer might not be making the seal.

Try taking the washer off and wrapping a few turns of ptfe just above the shoulder of the trap to make a 'thicker' seal.

Or is that what you have already tried :?:

Also water could be running down the thread if the waste isn't sealing.

Thanks for the swift reply Andy.

The top of the pipe for the bottle trap has a small flat lip that the washer sits on. I think the problem is the bottom of the waste which has no lip and is very narrow.

The water was coming down the thread until we put a basin mate at the top and reseated the waste in the basin. Now it's bone dry until it gets to the bottle trap pipe top.

The water is dripping down the pipe and seems to be appearing from between the nut and pipe however tight we fasten it (have even tried loosening it a bit in case it was deforming the washer).

There's no room inside the nut to place another washer as it won't then reach the thread on the waste to tighten.
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Does sound as if the washer isn't sealing.

Wrapping a few turns of folded up ptfe just above the lip of the trap instead of the washer should work.

If that doesn't work you could try some plumbers mait on either side of the washer. That should do the trick.


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