One of my showers has started to play up ... the temperature will not go above 35 degrees. The hot water supply is around 60-65. Almost certainly the thermostatic cartridge has failed - so looked for a replacement £160 each, Yes, one hundred and sixty. Before committing I called the manufacturer to check the exact part number. The good news - it is a ceramic cartridge and they have a lifetime warranty, so all I need is the proof of purchase/install and the replacement will be FOC - except for my time to install it.