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#4457
Been at at job where the sink stopper gets sucked down when an attempt to empty sink bowl is done after the stopper is slightly raised into its open position.
It is the stainless steel grid type with a rubber seal below it, possibly typical Franke type.
This has only started to do this and rubber seal appears to be as new.
No signs of where the waste goes outside from below solid floor, so I assume it is directly into a 110mm pipe below floor.
Any ideas what could be causing this?
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#4459
SimonG wrote:
January 29th, 2018, 8:23 pm
Creating a vacuum. Does it have an anti vac trap?
No anti vac trap there. Didn't look much below sink, but I do remember having to fix a normal P trap there a few years ago and it is still same.
Odd that it has just suddenly started to close off now. Unless the stopper seal has become more larger with age, although looks perfect.
The waste could be run a distance below the concrete in 40mm as well, for all I know, which would obviously create a vacuum.
I will try some drain cleaner later and it that fails, an Anti Vac trap is next.
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#4462
SimonG wrote:
January 29th, 2018, 9:24 pm
If It's like a strainer waste I think they have a sprung ball bearing that keeps it in place. The spring could have gone on it.
That's an idea. I think it is just the solid type strainer, with a rubber ring seal, but I will have a look at it when I go back.
I was actually only there to work at oil boiler.
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#4463
REDSAW wrote:
January 30th, 2018, 12:20 am
blockage in the overflow???

cant you adjust the plug higher aswell?
The overflow never crossed my mind! That is a possibility, if the waste pipe run is wrong and the overflow has now blocked, it would explain the suction on the waste. Will also look at the overflow.
The waste strainer plug is not adjustable. Possibly a Franke waste, or certainly similar.
Builders did the extension a few years ago and no doubt the plumbing is poor
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By REDSAW
#4464
Best wrote:
January 30th, 2018, 10:35 am
REDSAW wrote:
January 30th, 2018, 12:20 am
blockage in the overflow???

cant you adjust the plug higher aswell?
The overflow never crossed my mind! That is a possibility, if the waste pipe run is wrong and the overflow has now blocked, it would explain the suction on the waste. Will also look at the overflow.
The waste strainer plug is not adjustable. Possibly a Franke waste, or certainly similar.
Builders did the extension a few years ago and no doubt the plumbing is poor
Ah!
i was thinking basin waste :lol:
plunge waste and check air pumping to overflow easy enough. it would do it if it were blocked though as its tring to pull down the hole.
i havnt examined a ball bearing in the stopper before, thats intesting too!!
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#4513
Turns out it was indeed the sink overflow blocked.
It hadn't occurred to me.
I tested it today by filling to above the overflow level and it didn't take water away.
Removed the flexi overflow pipe and cleaned it and sink now drains without the stopper getting pulled down.
No doubt the waste pipe below floor (done by a plumber working for the builder) is incorrectly done and part of the problem creating a vacuum.
Wouldn't surprise me if it is a 40mm pipe below the screed for a long distance.
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By REDSAW
#4515
Best wrote:
February 2nd, 2018, 8:26 pm
Turns out it was indeed the sink overflow blocked.
It hadn't occurred to me.
I tested it today by filling to above the overflow level and it didn't take water away.
Removed the flexi overflow pipe and cleaned it and sink now drains without the stopper getting pulled down.
No doubt the waste pipe below floor (done by a plumber working for the builder) is incorrectly done and part of the problem creating a vacuum.
Wouldn't surprise me if it is a 40mm pipe below the screed for a long distance.
glad you got it sorted. nice to be on it. :)
id stick some drain blaster down it to be sure.

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