What kind of trap for washing machine only?

Washing machine trap:

A washing machine trap is a J shaped piece of pipe. Yes you should have one, else nasty pongs come out of the machine 24/7.

If the machine's own flexible waste pipe isnt too tight on length, its also possible to just tape it into a J shaped position and not have the fixed trap, but a pipe trap is best used.

NT

In message , harry writes

Like this:

WMs generally come with a plastic U shaped bit, which fits on the end of the waste pipe to give a nice up turned J shaped to hook over the top.

If you don't have it then just poke the pipe down into the standpipe a bit (not to far, you don't want to create a siphon. A bit of duct tape will hold it in place if necessary

I did this for a "temporary" connection, but it has been fine for 6 months. I cannot see why doing it more permanently could be a problem. I did wonder about stagnant water being left near the machine, but if you use a standpipe type arrangement, there will always be some water left in the machine itself anyway. Simon.

changed to a standpipe arrangement. They're OK for dishwashers though.

Brilliant - thanks all.

(Thanks especially dom for showing me something that was staring me in the face on the same flipping page as the one I'd linked to, but that I'd completely missed!)

The washing machine waste pipe no longer has an "umbrella handle", if it ever had one (I know what you mean - my mum's has one), so I'll probably just stick it in and tape it up like Chris said. Or can it be sealed to the top:

Does the trap have to dip below the level of the pipe that's running outside? Like this...

Cheers, David.