I did as you say - turned off all rads except the 2 not heating. Ran the system and after a few hours the rads statred to work properly. I was unsure about whether the air release valves on the rads should be slightly open or not. I left them open assuming that any trapped air in the line...
All radiators working perfectly until recently when I relocated a radiator in a downstairs room. Out of 10 radiators in the 2 storey house (5 upstairs and 5 downstairs) all are still working perfectly except for 2 in seperate upstairs rooms. I've bled these and the radiators did heat up. But...
