On Tue, 30 Aug 2005 19:33:49 +0100, Derek ^
wrote:


New professionally installed walk in shower. After being left unused
for a period on running the shower the shower tray fills up with
scummy bubbly water and gets practically to the point of escaping over
the ledge where you walk in. At that point we chicken out and pull out
the big chrome insert that covers the shower drain, and all the water
dissappears in a trice. Putting the chrome cover back in/on and the
water thereafter flows away freely untill the shower has been stopped
for a period (an hour or two?).

I can't find the exact shower waste fitting on the web but it's a
shallow chriomium plated plastic dome about 5" across with what looks
like a 3 sausage-segment air vent holes in the top, about 2cms P.C.D.,
waste shower water is intended to drain away under & around it's
perimeter. 'Cept it doesn't without that bit of persuasion. It seems
it might be at least similar to something called a "Fastflow" waste.

The walk in shower replaced the existing standard bath, but the waste
is perversely at the walk in end and the pipe had to be extended I'd
say the run to the soil stack is a bit over 3 metres and the fall is
less than the depth of the joists with one right angle bend. However
with the domed chrome insert removed it drains OK. If anything has to
be changed under the floor it can't be done, it's all sealed up :-(

I wasn't aware that these shower wastes were such a complicated affair
with concentric cups and sleaves. Exactly what it is all supposed to
do defeats me. Anybody come across anything like this before P.S.E. ?

DG


I suspect that the fall on the waste pipe is inadequate for the length
and diameter, given the waste fitting.

I remember reading somewhere (but can't find the reference now) that
some types of "mushroom" shower drain can capture a bubble of air but
that this goes through to the drain if the flow is fast enough.
Otherwise, the bubble causes the flow to remain restricted. Lifting
off the cap effectively removes this and allows full flow through the
trap.

The only two components that can be involved are the waste fitting and
the pipe, but as you say, they are sealed down.

Did the installer do the whole job? If so, or anyway, I would get
him back to fix it. If it does involve ripping the lot up, then I
would expect him to take the cost. He should have done the job
properly in the first place.




--

..andy

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