On Mon, 17 Sep 2007 09:42:07 +0100, Marky P
wrote:

I have just bought my first dishwasher, but my waste trap only has one
waste pipe connection which is being used by the washing machine. Any
idea where I can get an adapter to connect both pipes? So far I've
only seen complete waste traps, but I only need the bit that screws on
to my current waste trap with two pipe connectors.


Hello,

They say a picture is worth a thousand words, so I have included some
links. I have no relation to the company involved, other than being an
occasional customer.

You say that you have a trap being used by a washing machine, so does
it look like this:

http://www.screwfix.com/app/sfd/cat/pro.jsp?id=18640


You can get appliance adaptors like this...

http://www.screwfix.com/app/sfd/cat/pro.jsp?id=11180

....that allow you to connect appliance into traps, though I always
thought they were meant for sink traps rather than washing machine
ones.

Of course you could cut into the drain pipe after your existing trap
and fit a tee piece and add a second trap to that.

http://www.screwfix.com/app/sfd/cat/pro.jsp?id=73315


Does anyone here know the reason that washing mcahine traps have a
long length of pipe? I have three ideas:

1. It prevents back syphoning of foul water into the washer

2. If the washing machine drains faster than the waste pipe can
manage, it prevents flooding from the trap overflowing

3. Assuming they are fitted low down, it lifts the drain to a more
convenient height, that you can easily reach behind the washer.

Does anyone know which (if any) are right?
If (2) if both the dishwasher and washing machine drained at the same
time, could this be an issue?