Evening gentlemen. Got a strange one at work. One of the staff toilets keeps blocking up.It has a elbow pan connector into 110mm pipe which diappears into wall. When i flush it, pan fills and it then runs away ornot running as it flushes like it should, therefore not "washing down".Rite re moved WC and pan connector, no blockage can see app a metre in, then a bend. Thinking airlocking? Disconnected basin waste thats tee'd in to it to vent it still the same. Come on chaps im a plumber amongst other things. Why cant i figuer this one? Any ideas?????
Forgot to say when flushed i can see the water in the 110 as the sink connection i have removed is on top, but it doesnt run with the speed i would expect
Find the manhole it runs into & rod it from manhole back to the stack, could be a obstruction further down the pipe run.