I`m about to power flush a relatives central heating system, due to 3 of the 8 radiators not getting hot at all. I think the problem might be sludge/silt in the underfloor pipes. (The bungalow has a solid floor).
There are 12 pipes coming from the feed pipe just below the pump and I think they may feed each radiator separately, with one feed to going to the kitchen and WC next to it. The pump is in the airing cupboard while the boiler is in the kitchen. The system is about 14 years old and is not sealed.
I have already taken the radiators of and flushed them through so feel the problem is the underfloor pipes clogged up. Can somebody advise whether £140 spent on hiring a power flusher + associated chemicals would be the answer?