Shower controls not working and stiff All aspects of plumbing questions and answers, help, tips and information

[Hmh]

My shower controls are very stiff and almost fully seized when I turn the boiler and hot water on.

I switch off the hot water and ran it just on cold and it works perfectly, as soon as the hot water goes on the controls stick.

I have 2 showers, it is the same for both.

I did take one apart to make sure it was not caked in scale but it all seemed okay.

Please help!

[Drip-Doctor]

I assume when you took it apart you lubricated all the rubber o rings etc and bearing surfaces in silicone grease and tried to operte the internal workings outside the shower valve case so you could prove it worked before replacing? A photo would help, if not then perhaps a make/model of the shower or even whether it is an exposed and a concealed valve?