Grohtherm 1000 Thermostatic problem

[Micha]

Hi all
In my shower I have this unit.
We realized that all water system in the house is not warm as the boiler temp. After shut off the water to the shower the temp in all our valves rase up and work normal.
My understanding is that I have a leaking in the grohtherm between the cold an hot water when the shower is off.
Can someone help me what to check next?

 

[Exedon]

Picture of shower would be useful.

 

[Micha]

 

[HERTS P&D]

If it is the bar shower type, then just replace it.

https://www.screwfix.com/p/rize-exposed-thermostatic-mixer-shower-valve-fixed-chrome/491fv

Andy

 

[Micha]

It's not the bar shower. Look at the picture I sent.

 

[Micha]

https://www.amazon.de/dp/B00UALUE3M...t_i_VPB6RHKG2KT1TPHZ7TXT?_encoding=UTF8&psc=1

 

[Micha]

I sent link to the product but it's need moderator approval

 

[Exedon]

Needs taking out clean filters make sure what they call back flow preventer is not stuck if all good probably needs a cartridge.