airlocked rads

[pandaman]

I have just drained and flushed my open vented ch system after having X400 circulating in the system for a month.
The water coming out looked like oxtail soup! Anyway, filled up system but have 2 cold rads, one in lounge (a double) and the other in the kitchen. Have tried turning off all the other rads to try and force the flow through but no luck. What can I try next? If I turn off both valves to the rad, drain it again then open valves, to refill, would that help to cure it?
Any advice welcome.

 

[MANDATE]

If you have a mid position valve, then it should be latched in the middle position so both HW and CH ports are half open while filling to prevent air locks.
You did not state if you bled the radiators and with what result.
Also a closed valve will prevent radiator from heating up, maybe the lockshield valve, normally just open slightly is now restricted, considering you have been de scaling it.
Try bleeding with one valve closed and one open then vice versa. If it fails to bleed in any one of these situations you have a blockage (an air lock will not prevent bleeding)
You could also try increasing the pump speed

 

[Goldspoon]

Turn all off and open just a cold one.

If this fails... leave a day or two - situation may resolve itself.

 

[pandaman]

Thanks for advice, will have a go with your suggestions.