After replacing the small rubber seal on the shaft of the hydraulic actuator in my BIASI 24S Combi boiler, the two radiators downstairs turned cold, I bled the system, No result, then I drained the system, filled one of the radiators with cleaning fluid, after bleeding run the system over one hour, drained the system again, filled with inhibitor and bled again, after running the central heating for an hour, the result was the same, two cold radiators, will this have anything to do with central heating pump being faulty, not being abel to push the water through the system or is there a difficult to get rid of air trapped in the system.Is there heating pump setting that I could set to higher flow. Could you please help.

Al, March 2013

I did open both valves fully and also shut down other rads, the cold rad became hot, I left it for about three hours, I thought it did the trick, however when I opened all the other rads, it`s back to square one, it has gone cold or I should say, luke warm, which was from first place.

Al, March 2013

Make sure BOTH end valve on the rads that don't heat are fully open.then run system.you can also shut down other rads to encourage flow to other 2 as well

A1, March 2013