Grohe shower control leak

[Priory99]

I have a glass sided shower cubicle with Grohe 3000 Model 19255 thermostatic control valves and a flexible shower head, mounted on a tiled wall with all pipework concealed behind. If you have a shower the water drips into the kitchen below, about a quarter of a cupful. From below, because of RSJ’s and an original ceiling you cannot identify precisely the source of the leak, but:-

If you run the shower with the head in the bath-it doesn’t leak. So not the plumbing?

If you run shower with head in the basin and standing in shower-it doesn’t leak. So not the waste.

I’ve meticulously re-grouted the tiles and re-siliconed all the joints. It still leaks.

If you spray the shower on the controls, it leaks. I’ve reinstalled the cover plate and checked all the seals and as a last resort siliconed everything – all around the face plate and the controls themselves. It still leaks when you spray the controls!

Any ideas/help really gratefully received. I'm tearing my hair out.

 

[HERTS P&D]

Don't spray the controls?

Andy

 

[Priory99]

Thanks your helpful contribution. Its difficult though to have a shower and water from the head not hit the controls...

 

[HERTS P&D]

Post a picture of your shower control.

Andy

 

[Priory99]

I have a glass sided shower cubicle with Grohe 3000 Model 19255 thermostatic control valves and a flexible shower head, mounted on a tiled wall with all pipework concealed behind. If you have a shower the water drips into the kitchen below, about a quarter of a cupful. From below, because of RSJ’s and an original ceiling you cannot identify precisely the source of the leak, but:-

If you run the shower with the head in the bath-it doesn’t leak. So not the plumbing?

If you run shower with head in the basin and standing in shower-it doesn’t leak. So not the waste.

I’ve meticulously re-grouted the tiles and re-siliconed all the joints. It still leaks.

If you spray the shower on the controls, it leaks. I’ve reinstalled the cover plate and checked all the seals and as a last resort siliconed everything – all around the face plate and the controls themselves. It still leaks when you spray the controls!

Any ideas/help gratefully received.

 

[Priory99]

Sorry. Did something stupid and repeated original post. Here's a photo without the control covers. The space between the silver surround and the fixed portion of the black and white axles is now also full of silicone. It still leaks!

 

[HERTS P&D]

Do you find that when you stand in the shower, the tray slightly moves/flexs?

Andy

 

[Priory99]

No. Its a stoneware base and not very flexible. I have tried running the shower and standing in shower to see if any movement caused a leak at the seal or the drain, but it doesn't do so.

 

[HERTS P&D]

Post a picture looking at the side of the shower valve.

Andy

 

[Priory99]

Hi Andy, Here's a side view. Robert

 

[HERTS P&D]

Robert, where area are you in?

Andy

 

[Priory99]

The shower is in Twickenham, but I'm away now until 5th April. Having a rest while I think about it!
I'm obviously missing something.
My understanding is that all such Grohe controls should not need silicone on them at all. The seal is provided by the parts behind the face plate. Does anyone on the forum have experience of the controls themselves leaking when they are sprayed with water?
Thanks all your help. Robert.