I have a couple of stupid questions. (Actually, more than a couple, it turns out). Firstly, PTFE tape. Is it worth it (a lot of people recommend it; but many say it makes no difference. Who is right)? Is it stable enough to be used on the piping for the default radiator? What about the fittings on the back of the stove? Intuitively it seems to me that no part of the stove directly connected to water should ever get above 100 degrees, so PTFE tape would be okay. Is that right? Secondly, one of the plumbers we had in to quote suggested that we could handle filling the system, and dealing with overflow due to expansion, by teeing off from the default radiator flow piping, into a small tank with a ball-cock inlet, and overflow pipe outlet. That seems entirely reasonable, but I've never seen anyone else suggest it. Am I missing something?