We need to completely remove a downstairs radiator, is this likely going to entail draining down the system?
If so, would it be worth power flushing the system at the same time as I suspect it’s a bit sludged up?

Two schools of thought – you can get kit that will freeze both connections, and then the rad can be taken out without draining everything. I’ve never used this method though.

Easiest to drain everything out (there should be a drain cock somewhere that a hose pipe will fit onto) and replace from there. In my experience, sludge will sit in the bottom of the radiators and not in the pipes – the only really effective way to clean them out is to turn them on their side in the garden and blast out with a hose, and you really need to do this to all the rads at once to make it worthwhile.

Refill using a pot of corrosion inhibitor mixed in.

Depends if it has lockshield valves/TRV valves fitted; if they are you can just close them and drain the rad and remove.

When you remove the rad, be sure to close the bleed screw then turn it upside-down or you’ll get a trail of filthy black sludge across the floor.

Usually pretty easy to remove the rad without draining the system but if you want to cut the pipes back and cap them then you’ll need to drain it. Might as well clean it out while you are there. Drain point should be conveniently located. Mine is by the front door. If it isn’t then it’ll be a pain to drain but you can fit one so it is easier next time.

Ahhhh, should have said that the wall the rad is on its being removed so the rad and the pipework from the next room needs to go.

I’d just drain the system, not normally a big deal…..

Just remember to put back in some inhibitor when you refill (£7 from Screwfix).