Stupid Waste Trap Question

[Smiler.]

Please can someone assist in saving me from an effing straight jacket.

I have a P Trap for a washing machine connection. The vertical pipe connection is 40mm OD.

The horizontal connection however is larger (I'm assuming 50mm OD).

Is this then norm?

[GarryA]

The flexi pipe coming from the machine is smaller than the wastepipe fixed to the wall?

That should be ok.

[Smiler.]

No, the P Trap has 2 connections, vertical (in ) & horizontal (out).

The vertical has a length of 40mm OD pipe (into which the washing machine waste hose is connected) - all good.

The 40mm OD pipe does not fit into the horizontal connection, the pipe needs a slightly larger ID.

WTF??

Why would anyone make a fitting that requires a slightly different size connection on the in & out?

If there's a logic in it, I love to know what is it.

[Globs]

Photo?

If you are really puzzled, take it off, take it to a local plumbers merchants, and buy a replacement that works.

Those bits really are cheap as chips.

[dirkgently]

If you are talking about the hockey stick type the horizontal connector is usually inch & a half (bore tube).

[Smiler.]

Globs said:

Photo?

If you are really puzzled, take it off, take it to a local plumbers merchants, and buy a replacement that works.

Those bits really are cheap as chips.

So the same pipe should fit both ends then?

I'd just like to be able to buy something from a merchant without having to go all the way back there or to somewhere else to get additional bits to complete a job due to a problem that shouldn't exist in the first place.

Edited by Smiler. on Saturday 20th November 15:31

[Smiler.]

dirkgently said:

If you are talking about the hockey stick type the horizontal connector is usually inch & a half (bore tube).

Yep, but the 40mm is OD (35mm bore) which is why it won't fit.

[dirkgently]

Smiler. said:

dirkgently said:

If you are talking about the hockey stick type the horizontal connector is usually inch & a half (bore tube).

Yep, but the 40mm is OD (35mm bore) which is why it won't fit.

The hockey stick type come supplied with there own vertical tube which is a odd size.

ETA if you have lost the vertical tube you may have to buy a new hockey stick.

Edited by dirkgently on Saturday 20th November 15:47

Edited by dirkgently on Saturday 20th November 15:48

[Globs]

Smiler. said:

Globs said:

Photo?

If you are really puzzled, take it off, take it to a local plumbers merchants, and buy a replacement that works.

Those bits really are cheap as chips.

So the same pipe should fit both ends then?

I'd just like to be able to buy something from a merchant without having to go all the way back there or to somewhere else to get additional bits to complete a job due to a problem that shouldn't exist in the first place.

The problem is that you are there, looking at the problem. Me, and the plumbers merchant are not, and as a result have very little idea what you are talking about.

As the stuff is a) very cheap and b) very quick to fit, I suggest you take all the parts you can to them, ask them to sell you what you need, then come home and stick them on. If you are not sure of a part: take it with you.

[Ferg]

Smiler. said:

No, the P Trap has 2 connections, vertical (in ) & horizontal (out).

The vertical has a length of 40mm OD pipe (into which the washing machine waste hose is connected) - all good.

The 40mm OD pipe does not fit into the horizontal connection, the pipe needs a slightly larger ID.

WTF??

Why would anyone make a fitting that requires a slightly different size connection on the in & out?

If there's a logic in it, I love to know what is it.

WTF indeed. They are almost always a multifit connection, but it is possible that the trap you have is made for a specific (larger) size. Is it a pushfit connection or one with a nut and rubber olive?

[essexplumber]

Could one of the 42mm be that st B&Q sell that fits their pushfit fittings?

[chris1roll]

Remember that pushfit, compression fit and solvent weld pipes are different diameters, despite all being listed as 40mm.
You can generally wedge solvent weld pipe into a compression fitting (well, I did anyway), but a compression fit pipe into a solvent weld fitting won't work!
I've got 2 meters of compression fit pipe with about 15cm cut off the end before I worked that out and had to go back to B and Q

[Smiler.]

Ok, thanks to all who posted, I do appreciate it.

The solution is:

40mm OD (35mm bore) vertical pipe is not the same as 1.5" waste (38mm bore), which will fit the output.

Every website I looked at (that was open this afternoon) listed 40mm or 1.5" or 40mm/1.5" waste pipe in stock.

Clearly they are not the same (3mm difference) but I guess usually, it wouldn't matter (as Ferg pointed out - "universal" fittings)

I obviously bought the only type in the UK that wasn't, made by McAlpine & sold by Travis Perkins.

Anyhoo, washing machine plumbed in & running, so gonna have a pint of Rebellions finest & some ruby murry.

I bid you all bonsoir

[Simpo Two]

About time they standardised waste pipes/fittings; thundering nuisance.

[spikeyhead]

Simpo Two said:

About time they standardised waste pipes/fittings; thundering nuisance.

Blame the Europeans for that, it's not been good since we went metric. The French had the right idea and still just use imperial.

[Ferg]

Simpo Two said:

About time they standardised waste pipes/fittings; thundering nuisance.

When copper waste stopped being the norm some manufacturers produced a plastic system with the same OD. This was so that push-fit fittings could be used to join to existing. Bartol's 'Coppertone' was even the same colour (until sunlight got to it!), however due to wall thickness the bore was smaller and manufacturers decided to make a true 'clearbore' waste.

For this reason ALL solvent cement waste systems are the same. OSMA chose to upsize their push-fit at this time to the same size as the solvent system, but this is actually not such a good idea. Push-fit systems use polypropylene pipe which will certainly not cement with the cements used for solvent systems so the unaware can often make a joint that comes apart later.

Plumbers (worth their salt) will use solvent waste. Push-fit is cheap and nasty and the 'o'-rings (of course) don't stand up to the expansion cycles demanded of them (Speedfit watch and learn..), however PP pipe can take higher temperatures than ABS so it does get used for cylinder discharge pipes a little now that G3 has been relaxed to allow soil and vent termination as opposed to ground level.

[Simpo Two]

I seem to recall that Marley make '40mm' pipe that's about 0.5mm too big to fit other 40mm systems. A cunning ploy so you have to buy their kit no doubt.

Edited by Simpo Two on Sunday 21st November 13:40

[Ferg]

Simpo Two said:

I seem to recall that Marley make '40mm' pipe that's about 0.5mm too big to fit other 40mm systems. A cunning ploy so you have to buy their kit no doubt.

As above, Marley 40mm solvent waste fits ALL other solvent waste systems. If you don't mess about with crappy push-fit stuff you won't have problems with waste systems.

[Simpo Two]

I have used solvent weld. It's very easy, but you have about 3 seconds to get it orientated before it fuses. If it's too short or slightly off angle, you have to cut the whole joint out and start again - except that you may not be able to because it may be too short then. It's certainly neater than push-fit though. Neat yes, flexible, no.

[Ferg]

I've had bathroom floors up for pushfit after 4 years.

Best to do it properly first time. It's like making a fence out of wallpaper.