You should get about a bucket and a half form that one
did you turn the valves off with an adjustable spanner?
Can you open them again and close them again and try and seal the valves tighter
If the valves are nearly shut the radiator will not heat up
I turned what I believe is the inlet valve on the left clockwise as far as I could with a adjustable spanner. The valve of the left has a plastic cap over the top with small piece of metal showing through, same shape and size to the valve on the pipes I switched off and on when fitting washing machine (apologies, not familiar with terms!).
Did the other valve get turned off with an adjustable spanner - hand tight will not stop the flow
Valve on the left yes, valve on the right I just turned the plastic cap clockwise as far as it would go - do I need to break the cap off and tighten with a spanner?
It should pull off if there is not a screw in it
There is a v. small flathead screw in the middle. Is this likely to be the only issue? I'm not at home so need to do this tonight, I can remove the cap and tighten the valve - does water flow in both sides?
In and out both sides so they both need to be tight
Come back to me later once you have done this
Andrew - removed cap and turned clockwise as far as I could. Water still coming but I can now feel the radiator heating up now too (heating currently on).
Perhaps there may be grit on the seat of the valves?
You may need to drain the system and swap the valves for better control, this would be an ideal time to fit a TRV if not already fitted.