I have a twin valve thermostatic shower. An overhead "rainfaill" style head and a smaller hand held one on a hose. Been having problems with the overhead shower going hot and cold. Removed , cleaned and recalibrate the temperature cartridge but it's still intermittent.
The hand held nozzle seems fine, keeps a steady temperature. It also comes out at a higher pressure whereas the overhead seems a lot weaker.
Could this be a problem with the diverter valve or because the overhead is higher up?
Had the combi boiler checked and told it is okay.
Thank in advance for any advice.