I have the above boiler that is leaking from the central heating diff valve where the microswitch is attached.
I have searched the threads but most deal with the front diverter leaking. This is leaking from the top nut on where the microswitch touches the top valve.
I have attached some photos which show what it should look like (above)and what it does look like.
My query is can I replace the top part or do I need to replace all of it.
Is it likely to be the inside part many thanks..