Blocked drain.. Help..! Now with pictures. HELP

[jthorne]

OK.. I have a bit of a problem with my drain in the kitchen. But... its got me stumped…

It all started when I tried to wash some clothes about a week ago…up until then everything was fine…
I noticed that the washing machine still had about 2 inches of water in the bottom of it. When I looked closer I found the washing contained bits of food as well.
I put the washing machine on again and watched it go through the motions. When it got to drain I noticed that the sink in the kitchen (directly next to the washing machine) was filling up with soapy water. I stopped using the washing machine and left it for the day. Then that night I was doing the washing up. I let the plug out and the water half drained and then stopped. The remaining water took about half an hour to drain away. I came to the obvious conclusion that it must be blocked at some point. The washing machine output runs into the sink’s waste pipe about 4 inches up from the U bend. I took apart all of the white 2 inch pipe and the U bend but could not find anything blocking it. The house is only 3 years old and the pipes all looked like new inside and out. The only part of the pipe I could not look in was the last 8 inches or so. This was because when they built the house they built the kitchen on top of part of it and glued all the joints together. So…. I figured the blockage could be in there and that I would have to cut out part of the bottom shelf to remove this part of pipe…This morning I did that and discovered that the end of the pipe goes through a rubber bung and into a 4 inch pipe. The 2 inch pipe was totally clear… so I know the blockage must be further on down the 4 inch pipe. I got one of them flexible drain un blocker things. I pushed it down the 4 inch pipe and with a little bit of a wiggle I managed to get the full 15 foot of it down there… When I pulled it back there was a little…but not much muck on the end of it. So I thought I would go outside to the inspection chamber and try to poke it from the other end. I did this (in the chamber that’s about 6 feet from my kitchen sink) and again nothing was on the end of the wire. So I put everything back together and ran the taps. After around 1 minute the sink again filled up and was not draining. I looked in the inspection chamber and could not see any water running through it…

So im stumped. I don’t want to call a drain company out as im not sure what they can do that I have not already done….

So any advice would be fantastic. I’m totally stumped 

 

[jthorne]

anybody?

 

[noonespecial]

Well you have diagnosed the fault yourself - a blockage

Waste water will drain past a blockage usually after a period of time.

You really need to get a good plumber in to trace where it is and unblock it. There are all sorts of devices that can be used for the task but overall if you have been unable to rectify it yourself so far you are probably better off calling in a plumber. Don't go for an emergency call out company though - ask around and get to know a good local plumber. despite what you see on television - there are lots about.

 

[Agile]

I also recommend you get a no-fix no-fee person. Ideally someone who will quote a fixed price for the job.

A local franchise in London will unblock an outdoor underground drain for a fixed fee of £140 plus VAT however long it takes.

Indoor small drain pipes should be £50-£100 or so.

Tony

 

[jthorne]

ok... im even more stumped now...

I have just taken the 2" pipe apart at point 1 in the picture... I then pulled the plug on a full sink of water and it emptied throught the U bend and into a bucket in a matter of seconds...

Then I filled the sink again.. Using a bit of hose i sucked water from the sink and let it flow into the other side of the pipe (that goes off to the 4" bit) I managed to get 2 full sink loads down there and it never backed up... so I connected the pipes back together... another full sink load.. and nothing.. it took about 30 mins to empty it.

Im totally stumped... i now am not sure i have a blockage at all.. and maybe there is some problem with the way the pipes are laid out... this does not explain why it worked ok for 4 months though..

Can anybody see any problems with the way the pipes are done ?

 

[Agile]

Well I commend you on your skills with photos! It makes it so much easier for us to see whats involved.

All I can say is that I can see no reason why it should not work properly!

Oops, I had not remembered the picture correctly when replying, thanks to Nigel for allerting me below!

Tony

 

[Nige F]

Not sure about Agile`s "second Trap?" but you have got what is known in the trade as a Lash UP and as it`s on New Build ......I`d get the NHBC and their "guarantee " on to it...............That small waste should go to the manhole via a 100 mm. gulley outside the house..but for NOW..............you may have a grease blockage in the 100mm. pipe I`ve known rods to go through grease and it still sits there BUT..........get a set of Drain Rods for £15 quid @ B+Q and rod the drain with a screw fixed to the rod .should be in the kit.Let us know how you get on .I love new house builders

 

[Agile]

Try TWO kettles of boiling water poured very slowly down the drain from the sink.

Tony

 

[jthorne]

Thing is.. the water that I put down the pipes after the U bend seemed to go down very quickly... so it was almost as if there was no blockage.. I could also hear it running quite well.. when the pipes are connected up i can hear it going very slowly

I tried 7 full kettle loads of boiling water.. and it still is draining very slow

And new house builds...... tell me about it.. see in the picture were I had to cut out a slot in order to remove the pipe fully.. They built the kitchen on top of the pipe and only cut a hole big enough to slide the shelf over the pipe

Im stumped on this

 

[JohnD]

I'm wondering if there could be an air bubble in the pipe, most likely in that horizontal run under the cabinet. It's difficult to see how it could form, unless the pipe sloped upwards and/or there was a constriction caused e.g. by solidified fat.

An air bubble might form if the pipes were running full, but not if you were pouring water down the drain slowly.

Until you fix it, I'd suggest you take the washing machine hose off the trap, so the washing machine doesn't get polluted by tealeaves and diced carrot, and empty it into the sinks and (very important) block the spigot for the hose in the side of the trap (if necessary, you can buy an identical trap which comes with the fittings to close the side entry). After you've blocked that, you could try a chemical drain-unblocker and a good sturdy plunger (the plunger will not work if the washing machine entry is open, as pressure will escape down it).

 

[Softus]

I had a similar problem recently.

I didn't understand why my solution worked, and still don't, but all I did was to correct what was a negative fall in a section of 40mm/1.5" pipe. BTW, your 2" pipework - it looks like 40mm to me.

The symptoms were similar to yours - sink was slow to empty, and the contents tended to end up in the bath first. When I uncoupled the 1.5" pipe near to the stack, there was no problem at all draining away. I initially thought, wrongly, that must there was a blockage further down in the stack, but this was a shared stack with flats above, so this wasn't realistic.

In the end, I believe it to be an air locking problem. If the fall is wrong then water going one way meets air trying to get back - impasse.

Maybe the stack vent was blocked with pigeons? For all I know it was aliens nesting (get down, Slogger). I dunno - it's fixed now though.

 

[tawelfryn]

I agree with the air diagnosis. Maybe a back up of pressure? I don't like them "u traps" I would unscrew just below the washing machine inlet, and replace with a bottle trap, much better in my opinion.

 

[jthorne]

maybe air trapped is the fault... I have tried it without the washing machine attached and I still get the same problem...
The pipe the goes under the unit has a right angle on it that you cant see and then a small thength of pipe then another right angle... the small length of pipe runs in the same direcion as the strate bit for the U bend...

Maybe there is air trapped in that part and the bottom part and together they cause the problem.. or something.. i dont know..

Im going to go give something else a try.... Got the day off work to try and fix this...

How should the pipes flow? should the part after the U bend always slope down?

 

[jthorne]

you know what...... I think i have solved it...!!!!!



Here is what i did... i removed the fixed pipe from joint 1 untill it goes into the 4" pipe.... Then i attached it again but this time sticking out of the cupboard and into a bucket.... turned on the water and it was fine... so i bend joint 1 into the air slightly.. only by about 1cm... the lift caused almost instant blocking anf back filling into the sink.... i lowered it back down.. and then 1cm further down and it cleared the blockage and emptied the sink in seconds....

so... it looks as though the air was getting trapped.. and this was causing it to backfill.... the reason it must have worked for 4 months must be that something pushed the pipe up and caused this... it must have been strained down before to make it work....
so.. im going to strap something to it to hold it in the down position.. and see if that fixes it for good..

 

[Softus]

...replace with a bottle trap, much better in my opinion.

Bottle trap! Are you having a laugh? Those hideous things that clog up more quickly than a Dutchman at a family wedding?

The pipe the goes under the unit has a right angle on it that you cant see and then a small thength of pipe then another right angle... the small length of pipe runs in the same direcion as the strate bit for the U bend...

Maybe there is air trapped in that part and the bottom part and together they cause the problem.. or something.. i dont know..

Firstly, you don't have "trapped" air - when no water is flowing all pipework should be empty except for the trap. Secondly, I doubt that the pipework in the cupboard is at fault, because you have a vertical section of pipe - you can't get a better fall than vertical!

Can you ascertain the degree of fall in the pipe that's not in the picture?

How should the pipes flow? should the part after the U bend always slope down?

YES. I say again, YES!