Kitchen sink blocked

[Erik]

Hello, I've got a blocked sink. I've taken all the pipes immediately under the sink apart and removed any blockages there. Further down where the pipe goes down vertically before making a turn into the wall I've put drain cleaner in several times. This has helped a bit, but the water still doesn't go down. When I open up this vertical pipe (it's basically the top pip slotting into the bottom pipe, so it appears not a solid connection) and let air in the water does go down, but if it's a large amount I have to do this several times to clear the water completely. Water comes up into the sink when the washing machine or dishwasher drain water. Any advice?

Thanks very much.

Erik

 

[Best]

Where does the pipe terminate?
If it goes into a gulley, check the end of the pipe isn't blocked. It sounds like it is air locked a bit. Sometimes the pipe can rest on top of the grid on the gulley and be blocked with hair, leaves etc.

 

[Erik]

Thanks. I'm not sure. It comes from the sink to the back of the cupboard, then it goes down vertically (which is where I've been letting the air in) and then it makes a bend and disappears into the outside wall. I'm planning to go to B&Q at the weekend and get some tools like a snake (if that's what I need), but I want to arm myself with the correct knowledge so that I can ask the right questions to get the correct stuff.

 

[Rckape]

Have you checked or replaced the trap?

It sounds to me like that's where your problem is. Pop a bucket under the trap (U-bend) and unscrew it from the sink and pipe, undo the nut in the middle of the trap too and give a good clear out and wash in soapy water - remembering that if you turn on the kitchen tap, water will pour straight into your cupboard.

Then check the pipe outside as Best suggested. Blocked gulley/manifold or if it bosses straight into a soil pipe then there could be a blockage underground.

After that I'd be looking at replacing the whole lot. There's nothing else to them really.