Sink not draining, but no blockage?????

[angle]

I'm starting to go insane and wondering if someone can give me some pointers/advice/sanity please?

My bathroom sink is blocked and I've tried all manner of sink ublockers.
I also disconnected the u-bend at the end furthest from the sink, made sure it was clear and ran water through it into a bucket. All ok.
The pipe goes into the wall and along a bit (no more than a metre). I stuck a wire coat hanger in there as far as I could and cleared some stuff out, put some water in there and all seemed ok. Reconnect the u-bend and it's still blocked.
I accessed the pipe a bit further along and disconnected it and cleared out a little bit of gunk and ran water through ok. (this is with the u-bend connected to the sink again). Reconnected it all and the sink is still blocked.
I then disconnected the pipe at the next place I could and repeated process. Water runs from the sink to there ok, but when it is re-attached the water fills the u-bend, but goes no further.
There doesn't seem to be any blockage at all, but I cannot understand why the water still won't driain. Specifically I don't understand why the water won't go down a pipe I have just proved is clear.

Has anyone else encountered something similar or have any suggestions as to what could be the problem?

Many thanks.

 

[angle]

I forgot to mention that the shower, bath and kitchen sink are all working fine!

 

[Bahco]

Can only be a blockage, lack of air or inadequate fall caausing this.

Check again.

 

[Agile]

All I can say is that you dont seem to have been as effective as you imagine!

Have you put a pressurised flow through the pipe such as from a mains fed hosepipe?

Tony

 

[angle]

All I can say is that you dont seem to have been as effective as you imagine!

Have you put a pressurised flow through the pipe such as from a mains fed hosepipe?

Tony

Well I am a novice at all this.

No I haven't put a pressuried flow through, mainly because I don't have a hosepipe. What would that prove?

Thanks for replying.

 

[angle]

Can only be a blockage, lack of air or inadequate fall caausing this.

Check again.

What does inadequate fall mean?


Why wouldn't the water flow as far as the blockage?

Thanks for the reply.

 

[HERTS P&D]

Put all pipe work back together.
Get the garden hose and place it in the sink/plug hole.
Place a cloth around the hose/plug hole to block the plug hole.
Get some else to open the garden tap slowly while you are holding it in the plug hole.
This will be forcing water down the sink waste and hopefully push out any blockage.
Also don't forget to block the overflow.

Or use a wet vac to suck out the blockage from the sink.

Andy

 

[Hugh Jaleak]

All waste pipes rely on gravity to allow the water to flow, therefore are fitted with any 'horizontal' sections having a slight slope in the direction of low, this is known as the 'fall'. Inadequate fall means the pipe isn't sloping enough, slopes the wrong way or has a dip in it.

If the pipe is blocked then the air in the pipe is trapped, when you pull the plug the water cannot travel along the pipe as the pipe is still full of air that cannot be displaced due to the blockage. Where does the pipe go to?

 

[Agile]

Does anyone there have long hair?

Does anyone pour oil or fat into the drain?

Whatever you think if you are going to solve the problem then you are going to have to do something! The hosepipe is the best and easiest first try!

Tony

 

[angle]

All waste pipes rely on gravity to allow the water to flow, therefore are fitted with any 'horizontal' sections having a slight slope in the direction of low, this is known as the 'fall'. Inadequate fall means the pipe isn't sloping enough, slopes the wrong way or has a dip in it.

If the pipe is blocked then the air in the pipe is trapped, when you pull the plug the water cannot travel along the pipe as the pipe is still full of air that cannot be displaced due to the blockage. Where does the pipe go to?

Yeah I figured that out after asking the question
The sink has mostly worked fine for the 4 years I've lived here so I assume the fall is ok.

The pipe goes along (at a slope) then down, along again and disappears under the floor.

 

[angle]

Does anyone there have long hair?

Does anyone pour oil or fat into the drain?

Whatever you think if you are going to solve the problem then you are going to have to do something! The hosepipe is the best and easiest first try!

Tony

All hair is quite short and it's the bathroom sink so they better be no oil or fat down the drain!

Will see if I can get a hosepipe tomorrow.

Thanks.

 

[Agile]

The hosepipe might do the trick!

Perhaps you neighbour has one you could borrow? Always a good excuse to have a chat with the neighbour!

 

[Hugh Jaleak]

Do you know where the pipe goes after it heads through the floor? Or is it a ground floor room?

 

[angle]

Do you know where the pipe goes after it heads through the floor? Or is it a ground floor room?

It goes under the floor and out the side of the houes I think.

 

[Hugh Jaleak]

And where to from there?