Dishwasher waste pipe into ubend blockage advice

[radsmith]

Hello,

I have the dishwasher and washing machine waste pipes connecting with a "Y" type pipe connection which then goes through a u-bend and away.

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I thought i had a dishwasher waste pipe leak but instead, there is waste water coming out of the top of the Y connection through a hole which I think is an air hole (circled). If this hole shouldn't be there, well, there's the problem!

If the hole should be there, this makes me think that there is probably some kind of blockage at or below the Y connection that is making the waste water expel back through the hole.

The problem is in detaching the pipes in order to check and clean. The joints are all too tight to shift even with a pipe wrench. I will probably need to hacksaw through somewhere.

My questions:
1) If I do hacksaw, where is best to do so? I am thinking at the join on the top left just after the last bend section.

2) Is this a good arrangement for waste or should I look to put in a different pipe system?

3) If it is good, will plumbers putty suffice to seal the joints when I reconstruct the u-bend and re-attach (probably with new bends and pipe).

Thanks for any advice.

 

[Hugh Jaleak]

Air hole is meant to be there. Does sound like it is blocked i'm afraid. Those are 'solvent weld' joints, you will never get them apart!

Only solution is to cut through the pipe, either clear it and rejoin with a coupler or replace the entire affair with a washing machine trap, (better option for future maintenance).

Washing machine trap: http://www.screwfix.com/prods/18640/Plumbing/Wastes-and-Traps/Washing-Machine-Trap-40mm

 

[JohnD]

that collection of bits formed into a Y is not correct. The end of the vertical grey pipe should be open, with the crook of one waste hose tucked into it. Undo or cut off the white nut holding the Y to the top of the grey pipe. Pour water into the grey pipe and see if it drains away.

 

[radsmith]

Thank you both for your help. I will try the water method and see about changing the whole thing for the proper trap.

 

[Wangerman]

Thank you both for your help. I will try the water method and see about changing the whole thing for the proper trap.

Failing all of that try block buster 93% sulphuric acid but please treat it with respect

 

[radsmith]

Failing all of that try block buster 93% sulphuric acid but please treat it with respect

That seems like serious stuff! Cheers.

 

[Wangerman]

Failing all of that try block buster 93% sulphuric acid but please treat it with respect

That seems like serious stuff! Cheers.

It is but very good at clearing hardened soap powder etc. There is another product called Diamond Black which does the same.

It's ok to add it to water slowly but do not add water to it in large quantities as it can have a violent reaction and you could get covered in it. Just read the instructions carefully and you wont have a problem

really unwise to pour it down a toilet as the chemical reaction creates lots heat and I have seen a pan crack in half

 

[JohnD]

I find the strong detergents in dishwashers keep the pipes pretty clean. I wonder if someone has been pouring turkey fat down the sink?

 

[Whitespirit66]

really unwise to pour it down a toilet as the chemical reaction creates lots heat and I have seen a pan crack in half

Had a curry a few weeks ago from local Indian. Very similar effect!

 

[radsmith]

Perhaps the issue is that it's a shared pipe with dishwasher and washing machine, an inherited setup. More gunk buildup.

 

[Wangerman]

Perhaps the issue is that it's a shared pipe with dishwasher and washing machine, an inherited setup. More gunk buildup.

It's not brilliant but double appliance traps are quite common

 

[Wangerman]

really unwise to pour it down a toilet as the chemical reaction creates lots heat and I have seen a pan crack in half

Had a curry a few weeks ago from local Indian. Very similar effect!

 

[WabbitPoo]

the whole thing looks like a right lash-up. the waste appears to be tied to the feed with a cable tie; the cold isolator seems to have been gouged into the wall. my advice would be to sort the bloomin' lot out in one hit.

 

[radsmith]

the whole thing looks like a right lash-up. the waste appears to be tied to the feed with a cable tie; the cold isolator seems to have been gouged into the wall. my advice would be to sort the bloomin' lot out in one hit.

It could be better, you're right. I have taken the advice received here and replaced the pipework with a proper trap and so far, all is well. The other stuff is functional and trouble free so I will let it lie for now.
Cheers.

 

[WabbitPoo]

was it blocked after all?