While you wait for answers, we may have found some information which could help you.
Click here for Gainsborough Shower Engine
gainsborough sv 800?
Transformer for old Gainsborough Diplomat pump shower?
what KW is my Gainsborough ps1200 power shower as I need to replace it? Any?
Gainsborough 8.5 se hot/ cold water problems ?
Gainsborough 9.5 on/off switch repair?
Gainsborough 2000x leaking from bottom of copper cylinder ?