Washing Machine drains up into sink!!!!

[Daviddastidly]

Hi,

When i drain my sink, water tends to run down the washing machine waste pipe which is connected just below the sink before the U bend. When i drain the washing machine, the water tends to drain back up into the sink rather than round the u bend and out the drain pipe. I have unscrewed and cleaned all the pipes but it continues to happen. I don't understand why the water chooses to drain down the waste pipe rather than through the U bend and out the other side if there is no blockage? Is this a pressure problem? Is the positioning of the washine machine waste pipe and its connection to under the sink relevant to the exit of the U bend? Help much appreciated.

 

[John506]

Fit a waste check valve between the sink and washing machine.

 

[bengasman]

water chooses the way of the least resistance; reduce the resistance downstream

 

[JohnD]

the waste pipe layout is probably wrong. Post a photo of all the waste pipes please.

//www.diynot.com/forums/viewtopic.php?t=129539

There is also a chance of a partial blockage, especially if anyone has ever put cooking fat, tealeaves, rice etc down the drain or used excessive quantities of washing powder

 

[Daviddastidly]

for some reason my photo won't work pasted directly to the site, but if you follow the link below to kodak gallery you can see the setup

http://www.kodakgallery.co.uk/Photo...&sort_order=0&albumsperpage=&navfolderid=2008

Water prefers to go down the grey w m/c waste pipe (on the left) than round and out through the U-bend. I get a few gurgling noises, thats why i think this is a pressure / suction issue as opposed to blockage. Esp as i dismantled the parts and gave them a clean a few days ago, but the problem has got worse!

 

[Rico99]

David,

Quite hard to see properly, but it looks as though your washing machine hose comes from below the sink trap.

If so it should be coming from above the trap level with the underneath of the sink the dropping DOWN to meet the spigot.

Rico