Bathroom Sink help please

[ChrisA12]

I have a blockage in my bathroom sink, now going down at 1 lt every 5 mins. Took off the trap and no blockage. No blockage in the sink.
Wired the down pipe to about 14 inches and no blockage. This is the bit that confuses me, When I pour water straight down the down pipe it drains off at a reasonable flow. As soon as I put the trap back on and put enough water in to fill the trap the rest accumalates in the sink and drains very , very slowly. Could someone give me an idea what is wrong please.

 

[Dan Robinson]

Blocked sink overflow?

 

[ChrisA12]

The Sink is V and B and the overflow is built into the casting. 3 holes that
drain in to the plug hole. These are ok and not blocked. So not the overflow.
Thanks anyway

 

[Dan Robinson]

Never assume...

Check...

 

[ChrisA12]

Dan , I have checked . I have poured water into the overflow and it flows
out of the holes in the plughole

 

[Dan Robinson]

Well you either have a block somewhere - which we know you have; or you have a vacumn forming in the drain...

My preferred method of unblocking sink drains is to use my hoover - but I don't have an ordinary hoover...

Mines the daddy... http://www.numatic.co.uk/products4.asp?id=69&status=

 

[ChrisA12]

Dan , How does a vacumn form in the sink/pipe?

 

[JPC]

A machine for specialist operators requiring continuous collection and discharge of bulk liquids, such as: salvage work, flood damage, flat roofing, fire services and the like.

Above taken from the provided link -

Do you cause a lot of floods then ?

 

[JPC]

Its not rocket science

check the trap..is that clear ?

check the pipework..from the trap all the way to wherever it goes

 

[Dan Robinson]

Do you cause a lot of floods then ?

Asked for that really didn't I...?

I use it for draining large systems and tanks without relying on drain cocks and hoses - but it can do a pretty good job on blocks as ell.

Chris, Vacumn is perhaps the wrong phrase, but unless air can get into the pipe, it won't drain - that why you have vents on your house drains...

 

[ChrisA12]

Dan , the bit that baffles me is that when the Ubend trap is on the sink it drains slow but take this off and the drain off is a reasonable speed down the pipe.. So why does the Ubend Trap cause the drain off to go slower. ?As previous the Ubend trap is clear.

 

[Dan Robinson]

suck water into a straw, then put your finger over the end - water doesn't come out.

 

[ChrisA12]

Hi Guys
Found out the problem and sorted it. Gave the pipe a little poke with a pipe snake. Then got the good old dyson over the pipe end after the trap and turned it on. Out cam a cupful of limescale. Culprit the Cat. The dirty sod has been ****ing in the sink creating limescale in the pipe and trap.
I have now shot the cat and I can now use the sink again without waiting hours for the water to go away.
Thanks for your help