You want to isolate the radiator from the heating circuit by turning both valves fully clockwise. That will mean that no new water can flow into the radiator, or back out of it. The only downside to this is that the water in the heater has nowhere to go.
How do you isolate a radiator without draining the system?
How to remove a radiator without draining it
- Shut down your valves at both ends of the radiator.
- Open the bleed valve to depressurise the radiator, then close bleed valve once air has been released.
- Lay towels underneath each valve and slacken off each nut connecting the valves to the radiator.
How do you temporarily cap off a radiator?
First unscrew the nuts on either side of your radiator just slightly (the may be a bit of a leak, so have some towels ready) - and lift the radiator off the wall brackets. Then just lower the radiator to the floor. Then tighten the nuts up again, to stop the water leaking.
