Mike Barnes wrote:
The downstairs toilet used to flush OK but now the bowl fills with water
and then takes about five seconds to drain away, the water level
dropping about 3 cm below normal and slowly rising again to about 1 cm
below normal.

It seems to me that there must be a partial blockage somewhere, and I'd
prefer to sort it out before it becomes a total blockage. Any
suggestions?

From the back of the pan the pipe turns right, goes through a side wall,
then turns right again and goes into the side of a vertical soil stack
(total distance so far about 1 metre). The soil stack is only about a
metre long, being capped just above the junction. This unusual (and
possibly illegal) arrangement hasn't given any trouble before in the 15
years we've lived here.


You need to lift the nearest inspection cover in the garden to see if
you can see "water" backing up there.

I suggest you only open this after leaving it to drain for a good few
hours, as otherwise you may end up with "water" exiting the inspection
cover!

(Replace "water" with anything you have flushed down the toilet!!!)

Toby...