Hi all
Two questions on 40mm washing m/c waste..
Does it matter how high the elbow is that takes the pipe through the wall (or conversely how long the vertical leg is, if I raise the position of the elbow). Is it usual to put a trap of some sort at the bottom of this (my current install doesn't have one and I don't remember bad smells as a result)?
TIA
Phil
TheScullster wibbled on Wednesday 30 June 2010 12:27
Not really, with one proviso: if the elbow is too close to the top of a standpipe, teh force of the machine emptying can cause "gurgle-back" ie flooding out the top. Swept bends rather than elbow/knuckle bends help. I have 12" from top of 40mm pipe to bottom of swept bend, through the wall then another swept bend and it works fine.
With a sharp knuckle bend I'm fairly sure it would not work.
If it is plumbed into a closed sewer branch, you absolutely *must* have a trap.
If it goes into a gulley or hopper, you'd survive without but the trap would help reduce cold draughts in winter.
too vague, sorry
A trap is good practice, yes. Machines work without one but you'll get nasty drain whiffs at times. The trap can be nothing more than positioning the outlet hose so it dips below the waste pipe.
NT
"Tim Watts" wrote
Thanks Tim Just the info I needed. Discharges into gulley, but gulley connects after short drain run to combined water/sewer system, so will defo fit trap of some sort!
Phil
TheScullster wibbled on Wednesday 30 June 2010 16:20
The gulley will have a trap underneath too - you can tell by the standing water under the grate.
As I said, then a trap will help stop draughts and won't do any harm. Trap doesn't have to be right by the machine - I have mine the other side of the wall under the stairs for convenience - that type is called a "running trap".
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.