Possible to reduce flow of Geberit Sigma into pan?

[kpri981]

Hi. I've had a Geberit Duofix 112cm installed with the Sigma 12cm cistern, flowing into the Bauhaus Pier compact WC. On either flush - smaller or bigger - the water often overflows the rim of the toilet out onto the floor.

Can anything be done to reduce the flow from the cistern?

My dealer has mentioned a cup device, which I believe is "Cup for flush volume 4.5 / 3 litres, for Geberit Sigma concealed cistern 12 cm", part number 241.894.00.1. Geberit's website is a bit lacking in explaining exactly what this does, but I believe it reduces the flush volume from 5.8 / 3 litres to 4.5 / 3 litres. But if this merely reduces the larger flush volume and doesn't also reduce the flow, it won't help, since the existing 3 litre flush goes all over the floor. Any thoughts on whether this would help? Or whether there are other solutions? Currently I think the only solution is to replace the pan.

Thanks for any ideas!

 

[Daveydub]

A problem with the pan or the drainage? Does the soil pipe go downhill?

 

[kpri981]

Yes it's a new install, downhill. It seems to be such an eager flush that the water crashes up and around the rim, overflowing onto the floor. It doesn't seem to be a problem with drainage - it hasn't got as far as draining by then! I've uploaded the video to YouTube so you can see what's going on

Note the toilet isn't a Crosswater Pier as per my sales invoice - it's a Globo 43. They look identical though, I wonder if they're just relabelled.

 

[Madrab]

Very little you can do about that. if you reduce the flow you may find it has issues with removing solids in one flush. I would say that there may be an issue with the pan casting as it should be designed to ensure the flow of water doesn't cascade over the rim.

That being said, you may have to alter the under rim channel to stop the flow to the front of the pan where the 2 flows meet. Have a look under the rim and make up some plastic packers to fit into it and do some tests.

 

[just pumps]

Many years ago I had this problem with a high cistern and a pull chain, I made a plastic washer with a slightly smaller hole in the centre to reduce the flow entering the pan. The washer fits in the pan then the flush cone and flush pipe follows it as usual fitting.

 

[just pumps]

Many years ago I had this problem with a high cistern and a pull chain, I made a plastic washer with a slightly smaller hole in the centre to reduce the flow entering the pan. The washer fits in the pan then the flush cone and flush pipe follows it as usual fitting.

Fishing around today and came across this.
https://www.google.co.uk/url?sa=t&r...or-flushpipe&usg=AOvVaw3x59tMcwmW-5U0QuXcccSV

 

[kpri981]

Thanks. I think I'm just going to send the pan back and buy something else instead. It's still doing the following, with the 3 litre flush, and the cistern set to 4.5 litres maximum.

 

[kpri981]

I would say that there may be an issue with the pan casting as it should be designed to ensure the flow of water doesn't cascade over the rim.

I have had a feel around the inside of the rim, and everywhere is smooth except on the rear back towards the right, there seems to be a faulty raised bit. I've taken some pretty rubbish photos with my phone selfie camera - you can't really see the detail, but most of the rim feels completely smooth and reflects light smoothly like this:

but the rear right has this imperfection that you can't really see clearly in the photo, but you can see that the light reflection isn't smooth:


I suspect it's because of this that the start of the flush is breaking up the water flow and overflowing the rim.

 

[dilalio]

It’s a pan moulding problem.
Send it back for replacement but you’ll have to pay the fitter for a refit because it’s not his fault. Or introduce a restriction in the flush pipe... but that is bodgery!!

 

[just pumps]

Definitely a pan defect so the restricter wouldn't help this time however it has been available for a long time, guess you've never heard of it.

 

[dilalio]

guess you've never heard of it.

Never had need to ponder if such a thing exists!

 

[just pumps]

Never had need to ponder if such a thing exists!

What's your main line of work may I ask. General plumbing, new build. Gas heating servicing, bathrooms.

 

[dilalio]

Why?

 

[just pumps]

Was thinking along the lines of a person that installs has a different mind set to one who solves problems.

Nothing else.

 

[jeff the gasman]

Was thinking along the lines of a person that installs has a different mind set to one who solves problems.

Nothing else.

He knows his stuff.