Hey I am about to move in to a house with an old back boiler heating system, with a tank and cylinder supplying the hot water. I am wanting all this ripping out and replacing with a combi boiler. I know the back boiler/ heating system hasn't worked for a while. I was looking at replacing all the radiators too as they are old and rusty and I want a few of them in different places. My question is would a plumber be best starting a fresh with the heating pipework putting all new runs in? presumably using plastic. With me having the raditors swapped and a few in new positions.