Hi Guys,
Got a issue with a kitchen sink.
I Installed a new island kitchen sink not long ago and they have been having problems with the drainage of the sink. Basic Bowl and a half sink, standard mcalpine trap, small section of pipe horizontal out of trap then one inch half elbow, then another small section of pipe vertically which then goes into a main drain under unit. Simple.
Or so i thought.
Now when the customer drains the sink it takes for ever to drain, bubbles appear to come up.
Now this 4inch drain in the ground was moved slightly by a builder as this sink was newly installed in a new extension. The rest of the house doesn't have an outside vent pipe, it just has an AAV in the bathroom upstairs.
I have tried everything to get the sink draining properly, installed a small aav under kitchen sink, thought that might help, It didn't. Re piped it all, took aav off upstairs to allow air in, still nothing. I took drain covers off outside and water was definitely running from sink into drain (slowly).
Now I'm out of ideas as to why this is happening. My original thought was it needs some kind of outside vent pipe but I thought the aav in bathroom would be adequate enough, even when I took it off the pipe nothing was happening.
The builder claims he rodded the drain and there was no blockage.
There seems to be some sort of negative pressure build up as when I filled the sink, I drained it, then I cut the pipework under the sink unit and air was escaping out then allowing the water to flow out of the sink. But I can't understand how there is so much of a pressure build up even when I've got drain covers lifted or aav off.
Any help or ideas would be great!
Thanks in advance.
Got a issue with a kitchen sink.
I Installed a new island kitchen sink not long ago and they have been having problems with the drainage of the sink. Basic Bowl and a half sink, standard mcalpine trap, small section of pipe horizontal out of trap then one inch half elbow, then another small section of pipe vertically which then goes into a main drain under unit. Simple.
Or so i thought.
Now when the customer drains the sink it takes for ever to drain, bubbles appear to come up.
Now this 4inch drain in the ground was moved slightly by a builder as this sink was newly installed in a new extension. The rest of the house doesn't have an outside vent pipe, it just has an AAV in the bathroom upstairs.
I have tried everything to get the sink draining properly, installed a small aav under kitchen sink, thought that might help, It didn't. Re piped it all, took aav off upstairs to allow air in, still nothing. I took drain covers off outside and water was definitely running from sink into drain (slowly).
Now I'm out of ideas as to why this is happening. My original thought was it needs some kind of outside vent pipe but I thought the aav in bathroom would be adequate enough, even when I took it off the pipe nothing was happening.
The builder claims he rodded the drain and there was no blockage.
There seems to be some sort of negative pressure build up as when I filled the sink, I drained it, then I cut the pipework under the sink unit and air was escaping out then allowing the water to flow out of the sink. But I can't understand how there is so much of a pressure build up even when I've got drain covers lifted or aav off.
Any help or ideas would be great!
Thanks in advance.
