oh SOOOOOOOOOOOO, WELL THENNNNNNNNNNNN
this is what happens when you do everything alone^^ Now I'm curious about the counterarguments again
Do you actually want to help someone here or is it about something else? What is wrong with wanting to do something yourself, learning something in the process, and asking a community for support?
Then I'll make my first post here. I'm not building new, but renovating my wife's parental home. Some things were done by companies, others I am doing myself. For example, the main bathroom downstairs was done by a craftsman acquaintance who brought in a plumber. The small guest bathroom upstairs I am doing myself including the pre-wall element (Geberit Sigma) and additional installations.
This is more or less finished now and although I am basically a desk jockey, I can say it's not rocket science. On my Geberit Sigma is a Villeroy & Boch Architectura rimless toilet and it works perfectly. I would most likely suspect a problem with the toilet, which possibly does not "direct" the water properly.
So you shouldn't always badmouth everything just because it was done yourself. He didn't even accuse the plumber of installing the concealed tank incorrectly or anything.
I wrote an email to Geberit on Saturday and received a call about it today. The manufacturer said that there are apparently recurring problems with many of the particularly cheap toilets, especially the rimless ones, as they seem to be not mature enough in terms of water guidance. He recommended a product from a brand manufacturer, whether Villeroy & Boch, Keramag, etc.
Today I got a Villeroy & Boch O.Novo rimless (apparently the entry-level model from Villeroy & Boch), installed it, and flushed. It now works as expected even with the small cistern.
Over the phone, Geberit explained to me how the water pressure is directly related to the height (and not the fill volume!) of the cistern. Once this was clear, it was obvious what to get:
For the small cistern, a toilet designed for the lowest possible water amount (and therefore lower water pressure). The O.Novo is specified with 3/4.5 liters and so it works without problems on a cistern with low height like the Omega now.
I will return the model I already bought tomorrow – the hardware store has already expressed willingness to refund. That makes sense – it does not work properly on a standard cistern.