Hi, I have a balterley bar shower c 2008 that has failed. It only supplies scalding hot water. I suspect the thermostatic cartridge is either dirty or failed. The kind folks at Marktwo advise that the cartridge is obsolete (it is the one with grub screw at the bottom). Can anyone advise 1, if it is worth removing the cartridge to clean it. 2. How do i turn the water off to it? It is connected to a Salamander RS75 pump that has isolating valves on it. is it sufficient to switch these to the off position? If I switch off power to the pump will I damage it? If i remove the cartridge, clean & reinstall it and it is still faulty and needs replacing, will leaving the isolating valves switched off be sufficient or will I need a plumber to isolate the water supply. Is replacing with a real bar shower easy? All the fixings are in place at 150 mm. Any assistance gratefully received