Pipe under the sink leaking

Markp1984

Hi, I've just moved into a new property and noticed the little pipe meant for a washing machine /dishwasher (see where I'm pointing in pic) is pouring water each time I use the sink.
I have two questions, firstly does this suggest that there's a blockage in the pipework below this point and, if not, is there some something I can purchase to temporarily block it off? Thanks for any help, much appreciated. 

nofoollikeold

1. There would normally be a washing machine or dishwasher waste attached to that spigot.  Presumably the previous owners took the machine with them, disconnected it and left the open pipe.  Nice of them!
2. It looks like (can't be sure) a McAlpine trap (WM 15).  If so, you can get a stopper to go in the spigot, McAlpine 228532.  About 25 to 50P from a plumbers' merchants, £2.50 from Amazon.
3. As a temporary measure wrap insulating tape crosswise over the opening, then secure the ends of those strips by wrapping more insulating tap around the spigot.  Won't last very long, particularly with hot water.
4. On a completely different point, the red handled valve at bottom left of your picture is a hot feed for an appliance.  They are now nearly all cold feed only, and I would advise you to fit a blanking cap to the thread on the end.  Otherwise, if the lever handle gets turned accidentally you will have a hot water flood.  Screwfix 39553 is an example.  Make sure there is a fibre, or better, rubber, washer fitted to the inside.

Carrot007

The ribbed bit?

Yes you can get a rubber cap (may be plastic I have not looked in a while!) thing that goes over it. Though you may find buying the whole trap a lot easier (and looking at that brown goop up top might not be a bad idea anyway!)

(Mine look similar but has 2 ribbed ends, one is not in use as I am fine emtpying the water drawer on the drier (it's high up not one of those low ones otherwise I would look for a hose (it does support it!))).

Markp1984

Thanks for both replies, much appreciated! 

Jeepers_Creepers

To answer your other Q - does this suggest a blockage further along? The good news is 'no', so don't worry.

The bad news is that the reason the water backs out that spigot would appear to be due to a poor design of U-bend/waste.

If you look at this pic, the red line indicates what will be the filled level of that U-bend - the level the waste water sits at. Something weird going on - that level is way up beyond that hose connector's connection to the U-bend, and is even going partly up that hose nozzle section. So it's no surprise that, as soon as waste water begins to flow down that drain plug, it'll back up enough to come out the open end.

Bad? Yup. Guess what's worse? If you have a W/M or D/W hose connected there, some sink waste could go back into the outlet hose and sit there, being smelly and stuff. If your appliance hose falls away from the height at which it's connected, then that waste water will sit right down that hose - that's yucky.

There's surely summat wrong with that existing waste?

Jeepers_Creepers

Compare with:

neilmcl

As @Jeepers_Creepers mentions your waste is higher on the U-bend than the WM/DW waste connection so it's alwasy going to leak. Yes you can cap the WM waste spigot but you'd should really look at sorting the main waste out too.

Markp1984

I see what you mean! The red line pic makes sense to me. 

 I'll have to have a look and think about a good solution, really appreciate that you've pointed me in the right direction. 

 Thanks again for all the amazingly kind and informative replies.

neilmcl

Markp1984 said:

I see what you mean! The red line pic makes sense to me. 

 I'll have to have a look and think about a good solution, really appreciate that you've pointed me in the right direction. 

 Thanks again for all the amazingly kind and informative replies.

Well depending on how much room you have below you can extend the length of the waste by using a longer piece as picture above which allow you to lower the outgoing waste pipe connection below the WM spigot. A few inches would probably do it.

Jeepers_Creepers

The example fitting I showed above would help in two ways - the first is that the W/M connector is higher up, so further away from the water level, and the second is that the first vertical section is telescopic, so you can use this to effectively lower the rest of the U-bend even further away from the W/M nozzle.

See the 'main' waste pipe at the back to which the U bend connects? See how it's currently sloping upwards to meet the U-bend connector? That doesn't help, as it's this connection wot determines the internal water level; it's the high point that the water needs to get over to escape.

If you visualise it, if you lower the whole U-bend - ie by extending the telescopic section - that sloping main waste will start to level out. You stop when it's near-horizontal (you still want a little slope), or when you bump into that unit shelf! But anything you can do to lower the whole U bend like that, will also lower that main waste outlet connection and also the internal water level relative to the sink. Ie, further away from the W/M connector.

Mark, you can do this! If it just doesn't work out, you can at least refit the old U-bend and get the sink working again - whilst you come back on here and shout for help :-)

(Make sure you have a basin that'll fit under the U-bend to catch any drips...)