Biasi 24S Combi boiler

[KAZZ3]

I have two pipes in the hall way for installing a new rad. I know I have to drain the system first before uncapping the pipes. Firstly, I have read on sites so many different ways of cutting cold water feed off. Can I just cut off water by the filler tap or should this also be from the main stopcock. Also to drain via a long hose from the combis Main drain circuit cock. Or in the downstairs toilet near the combi boiler there is a drain valve, can I do it from there rather than from the combi main drain circuit?I will also turn off the ch system. the radiator system is open feeds so does it matter what pipe goes on what end to the radiator as I do not know which comes from the boiler and goes around the system as it is controlled by a wall thermostat. Thank you

[ChrisR]

They aren't connected to the water main .... see faq on filling loop, for background.

[Agile]

If you were clever you could isolate boiler and still have hot water while you are fiddling with your radiators.

Tony