Many thanks for replying Agile-in fact reading your excellent answers to questions was one reason I havejoined DIYnot!
First -although I am at present living in Hungary my home -house -is in England and its there my GEM lives.
I did wonder however if you could give any answers to my...
I have 14 year old GEM combi-dont laugh-its in good shape except DHW supply on off etc-cause (BGH) scaling of secondary heatex-
BGH will descale using sonic method but I can have it descaled using chemicals-its taken out and put in a chemical bath-BUT it may leak-drip when refitted -What should...