Rad Balancing / Lockshield Valves

[Freezer]

Hi, I previously had 2 cold rads and after some DIY balancing one is now working fine but the remaing one is still cold. I have had the cold one on, on it's own and it heats up fine so it is not a bleeding problem.

My question is by further balancing experimentaion should the cold one pick up? The inflow pipe up to rad is hot. Is there a minimum amount the lockshield valve can be closed on other rads without causing problems as I have adjusted a number and they are still hot but may have to do close more...

 

[ChrisR]

Lockshield valves nearish to the pump only need to be about 1/8th of a turn open! Keep closing the hottest ones. TRV's make life easier! If you have no flow at all, it would tend to point to sludge being in there.