Popping sink noise

[pamzer]

Hi
My kitchensink has two plug holes and a washer draining into the same set up. Sinks keep getting slow drainage and continuous popping noises - do I have a blocking somewhere? It’s a new build and has done this 3 times in the first year. One plumber changed the washer drain - another one put some stuff down the sink that nearly ruined the stainless. Temporarily cleared but keeps happening. Advice please. I’ve attached a picture

 

[CountryFan]

I'm not sure what you mean by popping, gurgling maybe, and could be the tee on the waste pipe and air. Perhaps an air admittance valve would help.

 

[pamzer]

When I put water down either plug hole it drains slowly then there’s a glugging noise a few seconds after, then it makes popping noises if that makes any sense

 

[CountryFan]

Ahh ok. So partial blockage by the sounds of it. Have the traps been removed and checked? Do you put anything like grease, oil etc al down there?

 

[pamzer]

No I haven’t dismantled anything - don’t put anything dodgy down there and have the sink plug trap thingy that stop bits going down

 

[CountryFan]

No I haven’t dismantled anything

Then the plumbers should have done it. The waste pipe needs checking properly for a backfall and for any blockages. Where does it terminate?

 

[pamzer]

I’ve checked the traps - is that the u bend bits? Nothing there - could it be the washing machine hose is blocked ? The waste goes out of the back wall to a drain in the garden ( the kitchen is first floor )

 

[CountryFan]

Yes the traps are the u bends. You initially said the sink is slow draining, so a blocked washing machine hose won't cause this. Might be the pipe layout or could be restriction in the waste pipe.

 

[pamzer]

All clear in the u bends - think it must be further down the waste pipe - washing machine is drainage is coming up I the sink now. Do I need to go outside to the grid and stick some rods down there?

 

[CountryFan]

Do I need to go outside to the grid and stick some rods down there?

If it's blocked there, yes, or rod upstream. Do you have any inspection chambers/manhole covers?