Unable to control temperature on mixer shower

[andy3131]

Triton Excellente Bar Diverter Mixer Shower.

I was looking for some advice. I am unable to control the temperature on my Triton Mixer Shower. The temperature on all the taps are controllable therefore I believe its not the boiler. The plumber has piped Hot to Cold and I turn toward cold to get boiling hot...when I turn toward Hot I get freezing cold. There is no mix and the change is fairly quick. Is the piping a problem? He insists that it is not. I have even changed the mixer and still the same problem.

Thanks.

 

[Burnerman]

Presumably this is a thermostatic shower?
Reinstate the pipe work as per the manufacturers instructions and I'm sure normal service will be resumed!
John

 

[andy3131]

Yes it is a thermostatic shower. The plumber is coming tonight to fix the pipework..I think he has fed into the cold runner for the hot and not checked it properly.