While I have a couple of radiators removed for decorating, I was going to take the opportunity to put a dose of Fernox (or similar) into the header tank before refitting the radiators. Would it be advisable to put some 'slude remover' in first? As far as I know the system has never had any sludge stuff in it. The house is 12 years old and I flush the individual radiators with a hose when I remove them for decorating. If the answer is Yes, do I put the sludge stuff in for a few days, drain down, and refill this time adding Fernox? Are there any better makes of these type of products as Fernox is the only one I have heard of?
TIA
John