Musical toilets.

[The Medway Handyman]

Weird today. En suite with WC, basin & shower. Boxed in soil pipe in rear LH corner. Shower to the right of it, basin & then WC along LH wall.

The shower waste 'gurgles' after a short while. Initially it drains OK, then the tray starts to fill a little bit, then air bubbles come up.

Running a tap at the same time as the shower transfers the 'gurgle' to the WC, which initially causes the level in the pan to rise.

Due to their position, I would expect the shower waste to be connected to the soil pipe via a boss and the sink to be connected to the WC soil pie - so the shower & sink waste/WC shouldn't be connected.

Can't see though, everything is boxed in & tiled over.

Plunged the shower vigorously, carefully poured some 'One Shot' in, no difference.

I have a feeling it may be air?

Only accessible part of the waste plumbing would be the shower trap.

Any thoughts?

[Phil L]

Water can only rise in the pan if there's water higher than it in the shit stack, or, in rare cases, there's a vaccuum, in which case it'll need a air inlet valve

They won't be connected, but if you're running a tap and the crapper's filling up, this is an indication that the stack's blocked and you are effectively raising the level of the blockage

It's probably air. If they want it fixing permanently, the boxing in will need breaking open and an air inlet valve fitting, unless you can get one outside. The stack can't already be open at the top or this would never happen

[harry]

I assume there has been no problems in the past? If not, sounds like a partial blockage somewhere If you have drain rods and the flat rubber circular thingy that fits on the end.

Block off shower and wash basin drains, Use the plug and get someone to hold down or use a rag with someone stood on it.

Get a single drain rod with the flat thing on the end to use as a plunger, flush the WC and immediately work the plunger back and forth in the WC pan to scoosh the water as violently as possible. May clear it.

Is there a rodding eye outside? I may be necessary to dismantle the soil stack outside or put rods down the vent/rodding eye if there is one

[harry]

Also lift manhole cover(s) outside & see if all seems normal when toilet is flushed.