U-bend bottle trap nightmare!

May 22, 2009 14 Replies

I'm new to plumbing and hit a snag today. I don't know if I'm lacking a technique or the bottle trap U-bend I bought is crap:



The trap is supposed to fit onto 40mm waste pipe via a wedge shaped plastic slip washer and a big plastic ring nut. For a start I had great difficulty getting the nut over the waste pipe - the fit was incredibly tight - it left score marks on the pipe as I forced it on! The washer itself was worse. It took twenty minutes of wrestling to get it onto the



40mm pipe. (I put it on the correct way around). Next I was supposed to slip the pipe into the trap and tighten the nut. The only problem was that everything was so damn tight to move. The nut went cross threaded trying to slide the washer up and it jumped threads rather than pull the washer tight into the trap.

Was this just a badly designed trap? The tolerances seemed way too tight to me. Or am I lacking a technique here?



In the end I sawed off the screw threads and used some PVC waste pipe glue to attach it to the 40mm pipe. Not the best job I've ever done. Not a lot of overlap on the join for my liking. I'll test it for watertightness tomorrow, but wouldn't be surprised if it leaks; it certainly won't be very sturdy.



On the positive side, with the rest of the plumbing - all the solder end joints I've done have worked great. Must have done 80 joints and not a single leak! Very pleased as this is my first plumbing. Pity about the bottle trap.


David in Normandy coughed up some electrons that declared:

I think so. All the fittings I've played with like that have been fine - no where near having the nut bind on the pipe.

You might get away with it. Solvent weld is basically making the two lumps of plastic "as one" - better than gluing (where glue binds to surface with a dissimilar material).

Can you come and do mine?

;->

One of the parts must have been wrong, it shoud have been effortless to assemble

NT

In retrospect I think that when the packaging says the outlet is 40mm that is exactly what they mean. In other words the trap isn't intended for waste pipe of 40mm external diameter - it is probably intended for pipe with an external diameter of 38 or 39 mm diameter - if such PVC waste pipe actually exists!

Pushing a 40mm pipe into a 40mm hole doesn't work - well it does if you push really, really hard and curse and swear a lot while trying!

I've got another identical bottle trap for the bathroom upstairs so will take it back to the shop and exchange it. Trouble is the damn things are in sealed packaging so you can't do a test fit in the shop with a bit of pipe, you can only go on what the packaging says. I assumed 40mm outlet meant it took 40mm waste pipe; but seemingly not.

Dave, I've struggled with those components as well. But I've looked at a few recent bits in the 'paid for' work that we've had done and repeated it in the DIY bits.

All the wastes were done using flexible 40 and 50 -ish mm (like big washing machine waste hose, white, about 60cm - 2ft long) but using the wedge shaped washer and the ring nut from the component. The bottom end of the flexible waste is smooth plastic and fitted with solvent into the fixed pipe.

(I bought mine from Leclerc but I've seen them in Mr Bricolage, Leroy Merlin et al.)

In our local sheds you can tear the plastic wrap and try the bits for fit - just wait until no one's looking ;-)

Don't know if this is of use John

This all sounds like a mixture of things.. Did the trap come with the nut sealed in a bag? It can happen that you pick a split bag out of eg B&Q racks or a warehouse guy will just bundle anything he finds from a 'returns' rack. Either way, perhaps a

32mm washer got thrown in with a 40mm trap is strong possibility. Perhaps also, the new trap has a different height between bath thread end and outlet. This would result in the waste pipe being out of line with the trap outlet. This would make fastening the waste pipe nut very difficult and I've had experience of this. Also, even when trap and waste pipe are perfectly aligned it is easy to cross thread. But jumping threads seems unlikely so going back to the first point I made..perhaps the nut is a weird non-match. Did you try the nut to the trap before starting the fit?

Arthur

Is your waste pipe 40mm push fit/compression or 40mm solvent weld? They are slighly different, at least in the UK.

Why didn't the fact that you where having a right battle raise the "somethings not right" here flag?

You should not have a battle to get the pipe into the fitting. Indeed correctly matched components and a bit of lubricant on the pipe and even compression type joints can be assembled without taking apart. Slacken everything off, gently push the pipe in, tighten up.

As others have said it should be a cinch to loosely assemble, push onto pipe and tighten. my problem with the damn things is not buying an anti siphon model. The fancy chrome jobbie I bought from Screwfix siphons empty and lets the drain smell in. Of course changing it involves dismantling some very expensive units to do it but it looks as though there's no other way to do it.

Jb

You can convert a non anti-syphon to an anti syphon by adding a biro barrel. If you open an anti-syphon trap you'll see what I mean.

NT

Excuse me, I'd like to buy this but I just need to be sure it'll fit this 40mm pipe. Can I check? Well, we're not allowed to open them OK, I'll just have to leave it then Er, ok then, let me open it for you

NT

Snip

Really?? right thanks for that I'll have a look and see what I need to do.

Jb

In fact most have a plastic 'anti extrusion ring' behind the rubber seal to stop it being forced into the gap between pipe & nut.

Fine untill you want to get it apart :-)

I think you may have hit the nail squarely on the head! I bought the trap from Leclerc. I bet it is supposed to take that flexible hose not a

40mm fixed pipe! Where the packaging says 40mm outlet that must mean the size of the outlet hole, not of the expected pipe diameter!

Anyway, after testing this morning, no leaks! I'm amazed!

:-) I was quite impressed yesterday when I bought a new silencer for the mower - although it was packaged, they'd put a suitable hole in the back of the packaging so that you could check that the silencer's hole size and threading matched the pipework that you wanted to screw it on to. I wish more manufacturers would think of stuff like that...

cheers

Jules

welcome to waste plumbing french style

I took months to get fittings sold by toolstation who really ought to know better to work without leaking.

Wrequin make a really nice Quick clac bath waste which toolstation sell and toolstation also sell a shallow trap Alas the trap uses an o ring to seal on a groove and the clic clac uses a flat washer on a flange. This means the tighter you do it up the more th o ring leaks. This concept was too difficult for toolstation warehouse staff who investigated my complaints to understand.

I then obtained a Wrequin shallow trap which has the same problem as you describe. The UK waste pipe will simply not fit in. It transpires that french measure 40 mm OD and we measure 40mm inside ( probably because 1 3/4 * 2.54 comes to 44mm

The only solution to this sillyness was to use a solvent waste adapter which Wrequin will supply seperatly and use that

What stupidity of toolstation to still be selling only a combination of products likely to flood bathrooms even after they have been told by relying on their half witted staff HTH Phil

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