In article , John
writes

Remember that the radiator will be at pressure so you cant prevent it from
****ing out some water by just closing the valves and the air vent.

I did wonder about that but they suggest you release pressure on any
trapped air by opening the bleed vent first and then closing it before
opening the drain screw over a drip tray and fitting a hose

Possible faff, but they are dinky.
--
fred
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