how can i fix my boiler model worcester celsia 24le?

The filling loop may have been removed (which is correct proceedure) there should still be the fittings to attach one, it has to have been filled initally!

With low system pressure your boiler WILL NOT OPERATE pressure needs to be 1-1.5 bar when cold

If you cannot locate the filling system, you will need to call out a plumber, eitherway, the fact your system pressure has dropped so low would indicate a leak or a fault (safety valve or expansion vessel) that will also have to be addressed

T
June 2008