Check out some similar questions!

zzip2004 · Jun 8, 2012, 03:11 PM

When I moved into my flat there was no shelf under the sink due to the plumbing for the sink, washing machine and 0.5 bowl sink. My brother who works with a plumbing firm suggested a "flat trap" which enabled me to put in a shelf because the plumbing was not as low down. My question is, where the connection for the washing machine waste connects under the sink and into the flat trap is it enough of a drop for the waste coming out of the machine to drain away quick enough or could this connection be too slow for the waste to drain away and maybe go back down into the machine and possible damage the pump? The water sometimes comes up into the sink for a few minutes then drains quickly away and I never have a problem with the water draining away from either sink when doing dishes etc. I have included a picture how it is set up

Thanks

Stuart

speedball1 · Jun 9, 2012, 07:45 AM

Please explain what makes a "flat trap" different form a regular trap. A image would be nice. You are talking about a washing machine and not a dishwasher aren't you? Back to you, Tom

zzip2004 · Jun 10, 2012, 12:13 PM

Originally Posted by speedball1

Please explain what makes a "flat trap" different form a regular trap. A image would be nice. you are talking about a washing machine and not a dishwasher aren't you? Back to you, Tom

Yeah mate its for a washing machine, a flat trap is quite a thick bit of pipe with rubber flaps inside and its as if the u bend is inside the thick tube, here's a picture as well of the set up

speedball1 · Jun 10, 2012, 05:22 PM

No wonder I had to ask. Mechanical Traps are outlawed in every code in the States. How do you prevent the washers tub from draining if there's no stand pipe and the drain opening connection is lower then the washer tubs discharge point? Back to you. Tom

zzip2004 · Jun 11, 2012, 11:40 AM

Originally Posted by speedball1

No wonder I had to ask. Mechanical Traps are outlawed in every code in the States. How do you prevent the washers tub from draining if there's no stand pipe and the drain opening connection is lower then the washer tubs discharge point? Back to you. Tom

It is not a mechanical trap, and it is more common in the uk for a washing machine to discharge under the sink than using a stand pipe, in fact under the sink is normal practice, and as you can see from the picture the grey washing machine waste hose comes down from a higher height than the waste connection under the sink so water should not flow back into the machine and the waste pipe from the machine comes out of the bottom of the machine, again the norm in the uk, not half way up or the top of the machine.

massplumber2008 · Jun 11, 2012, 11:59 AM

Hi Stuart

If the trap has moving parts (rubber flaps) then technically, it's a mechanical trap in our area... ;)

With that being said, as long as the washing machine hose loops higher than the kitchen counter top then I see no issues with backflow or water standing in the sink.

You should be all set here...

Mark

zzip2004 · Jun 11, 2012, 12:33 PM

Originally Posted by massplumber2008

Hi Stuart

If the trap has moving parts (rubber flaps) then technically, it's a mechanical trap in our area...;)

With that being said, as long as the washing machine hose loops higher than the kitchen counter top then I see no issues with backflow or water standing in the sink.

You should be all set here...

Mark

Thanks mate