Well, there is now another leak coming from the boiler.  I have fixed the previous 2.  I am worried that eventually the pipes will burst.  
I am still convice that it's a matter of re-balancing the pressure in the system, but i just cannot do it, and the 3rd supposedly engineers have come out, and i know more about the boiler than they do.  So not much help there, cannot keep paying for service charge whenever they come out.  I have already spent £250/-. 
I still believe that my boiler can be fixed.  But need someone who genuinely know what they are doing.
                
 merv
                
 January 2007