On 27/04/2021 23:24, Steve Walker wrote:


We fitted a shower (with switchable, large, rainfall head and normal,
flexible hose head) into a cubicle with a low tray (about 15mm deep),
although the bottom rail of the door opening does add a further 10mm),
as my wife is disabled and so low is good. The shower is supplied by a
Grundfos pump with a capacity of 50-odd litres per minute at low
pressure, but more like 20 lpm with the back-pressure of the shower.

I fitted a hi-flow waste, rated at 31 lpm. As long as the trap is
cleared of hair every couple of weeks (there are 5 of us), it works
fine. Even if it does start to clog, the water level rises a little, but
that increases the outflow, so it doesn't get too high - and you get a
few days' warning to clean it out.

Same sort of experience here, though not with a hi-flow waste and a
Stuart Turner, I think it's a 2 bar one. That gives a very adequate flow
through a standard (not rainflow) head, if you have to throttle back
slightly against rising water level that's the sign that the pipes need
clearing. I don't have an accessible trap, but one of the low profile
"smooth bend" types. I use a hand-pumped "blaster" to clear it
periodically, sometimes adding some bleach or sodium carbonate overnight.