Connected new cistern, button makes mooing noise, no water

27 Jan 2004
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United Kingdom

Hope somebody can offer some urgent advice!

We have finally connected up our Grohe Eau 2 cistern today after biting the bullet and cutting down the pipes to make it flush to the false wall which contains the cistern itself.

Foolishly I pressed the air button in before any water was in the cistern but I don't think that is my actual problem.

The cistern is now full of water. When you hold the dual flush button in constantly there's a mooing noise and some water eventually trickles into the toilet. The cistern then refills. However, I cannot get the cistern to flush on the small flush or the large.

The mooing noise is quite loud and I'm worrying that by holding the button in I'm doing some damage to the cistern. Simply pressing the button in and releasing does absolutely nothing.

The Grohe instructions must be one of the worse sets in history. The cistern is in a tiled false wall but the top is completely open as we haven't put the shelf on yet.

Anybody have any ideas if there is a clip I need to remove inside the cistern to make it flush? I can't think what else it can be. :cry:
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can you lift the flush valve manually from above the cistern?
is there a small hole in the air pipe?
are the air pipes connected around the right way?
if you close the inlet valve and try flushing does it still make the noise?
We've just pulled the pan out and out came a load of water on the floor so it must have been released but not come through the pipe for some reason.

I'm afraid I don't know how to lift the flush valve from above nor how to close the inlet valve :oops:

The blue air pipe was connected at the bottom when the cistern was delivered and we've connected it to the back of the button.
part No 42 235 is the isolation valve. not clear on drawing but a flat blade screw driver should turn it off.

if you lift the inner cylinder of part 42 314 it should slide freely up then drop when water has been reliesed.

if you remove the push button and remove the distance washer does the button operate correctly?

you may have the flush pipe set a bit low and its holding some water.
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Thanks for the assistance :D

It was jammed so I suppose I should have put a bucket underneath it before I launched 6l of cold water onto my bathroom floor!

I've now managed to reconnect the toilet to both the soil pipe and the cistern but there's water leaking from somewhere. Too late to sort out tonight but I'll have to try to work out what's happening tomorrow and sort it out.

Thanks again :p

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