Vertical Radiators

Well you cant really do that without draining the rad first then removing it off the wall.

You're opening up a can if worms if you try to do this yourself. You need an engineer ti do it for you. You can potentially turn off the lockshield and trv (depending on what trv it is). Drain the rad through a nut with a wetvac and remove it. But if you or anyone knocks that trv a tiny bit you've flooded your house. Ideally an engineer would draindown for you, remove rad. Go do another couple jobs then come back to refit it for you.

Yes, if you simply undo the radiator unions, the water inside the radiator will come out. However, you can usually remove the radiator without draining the whole heating system. For a typical vertical radiator: 1. Turn the heating and boiler off and allow the system to cool. 2. Close the TRV (thermostatic valve) fully. 3. Close the lockshield valve on the other side. Before turning it, count the number of turns to fully closed (e.g. 1¾ turns) so you can set it back to the same position afterwards. 4. Place towels and a tray underneath. 5. Open the radiator bleed valve slightly to release any pressure. 6. Loosen one union nut carefully. A small amount of water will come out. 7. Drain the radiator itself into a tray or container. A wet vacuum is very useful for this. 8. Once the radiator is empty, disconnect both unions and lift the radiator off the brackets.

If you feel confident enough to attempt this rather than get a engineer out its relatively simple : 1. First you need to close both the valves lock shield and thermostat 2. I’d highly advises you purchase a wet vacuum screw fix 40quid 3. Radiator side of either valve crack open the nuts both sides Hoover on at this point focus on most accessible side and completely remove the nuts both sides and vacuum out the water. Be careful and ready to reconnect the nut if the hoover gets full. Once drained undo both sides and remove the radiator. To reinstall Hook radiator to brackets Reconnect the connections you undone making sure they are tight Open valves and open the radiator bleed valve to let the air out and allow radiator to refill. If you have a pressurised system just che ck system pressure once refilled make sure it’s between 1-1.5 bar of pressure